Comparison of a Samsung Galaxy S6 unlocked by Japan's big three carriers

As expected, Softbank Mobile announced that it will also adhere to the new guidelines and begin unlocking phones brought new to market from this month. This includes the Samsung Galaxy S6 Edge. The terms are exactly like Docomo's: unlockable from 180 days after purchase until 90 days after the phone is disconnected. Unlocking within that 90-day window for an out-of-contract product will also require a trip to certain softbank stores and therefore cost ¥3,000 plus tax.

Unlocking terms by carrier

	KDDI	docomo	Softbank
Cost	Free (¥3,000+tax in store)	Free (¥3,000+tax in store)	Free (¥3,000+tax in store)
Applicable to devices released from	April 23, 2015	May 1, 2015	May 29, 2015
Wait time to unlock	180 days	6 months	180 days
Unlock possible after cancel service	forever	for 3 months	for 90 days

Galaxy S6 Edge Comparison

Right now, the only phone that will be unlocked by all three is the S6 Edge.

	KDDI	docomo	Softbank
Cost with MNP (without)	¥33,480 (¥55,080)	¥29,808 (¥58,968)	¥21,600 (¥53,760)
Earliest unlocking date:	October 20, 2015*	Now	November 25, 2015
Unlock cost	free	¥,3000	free
LTE Bands:	1, 3, 18, 26, 28	1, 9, 19, 21, "700"*	1, 3, 5
WCDMA (3G) Bands:	1	1, 5 (or 6?), ?	1, 5, 8

* The exact bands are ambiguous. docomo simply lists "700" which could be one of 12, 13, 14, or 17 or perhaps all may be covered because the frequencies are either adjacent or overlapping. Also, both KDDI and docomo list support for "800". KDDI specifically states this is band 18. I believe that docomo uses band 19. The uplink frequencies are overlapping and the downlinks are close but not adjacent.

Figuring out which bands are supported

KDDI is the only carrier clearly indicating this an in easy to understand way. Their bands are published here. Softbank's are on the product's specs page (SBM S6 Edge). Docomo's are also listed on the spec page, but only for LTE (DCM S6 Edge). To get the 3G bands is a real pain, but docomo will be required to make this more transparent once they release phones under the new guidelines.

Docomo classifies the S6 Edge as a "class 5 world wing" device, which looking up here gives contradictory information. The product pages lists LTE bands "2GHz, 1.7GHz, 1.5GHz, 800MHz, and 700MHz". However a class 5 world wing device supposedly supports LTE Band 1 (2.1GHz), Band 3 (1.8GHz) and "others" such as Bands 4, 17, 20 "etc" as well as "3G" (whatever the hell that means) and "3G850".

LTE（Band 1（2.1GHz）、Band 3（1.8GHz）、その他（Band 4、Band 17、Band 20など））および3G、3G850、GSMネットワークをご利用になれます。

I'm just guessing here, but since the most common 3G band (except in North America) is Band 1 (2100 MHz), I am guessing that "3G" refers to Band 1 and that 3G850 refers to Band 5 (Actually I'm told that what docomo calls "3G850" is actually Band 6). I also assume that it doesn't support AT&T's Band 2 (1900 MHz, aka PHS) or T-Mobile's Band 4 (1700/2100 MHz, aka AWS).

Digging ever deeper into docomo's i–mode-like labyrinth of a website confirms no support for 3G in North America.

NTT Docomo to remove 3-day 1 GB limit on LTE data

All  of the Japanese carriers, in addition to having a monthly cap on data usage, also implement controls on short-term usage. This is because they lack the infrastructure to support an enormous instantaneous demand. In the past with other carriers, this has caused a tremendous amount of confusion due to inconsistent and improper communication to customers regarding these throttles. (Actually, it was probably because this particular carrier was making things up as it went along.)

To make matters worse, these throttles can be ridiculously implemented, where if you exceed a certain amount of data over a certain period of time, you get throttled, but not immediately. Instead, the throttle goes into effect up to 2 months later. That has nothing to do with network management and is purely punitive. I'll be glad to see these go.

Docomo Repeals 1 GB Limit

Docomo's limit was 1 GB over 3 days for Xi LTE data. Exceeding that results in a drastic speed decrease on the following day.

Xiのエリア拡充が進み、速度制限を無効にしても、お客様が快適に利用できる環境が整ったため

With continued expansion of the Xi coverage area, we can now provide a good user experience even without speed restrictions.

So Docomo will remove the restrictions. Yay! (There's no word on when, however.)

The 366MB 3-day limit on FOMA data will remain.

What about Softbank and KDDI?

Softbank and KDDI have commented that, at the present time, they have no plan to also remove their data limits. So that means they are now scrambling to figure out how to remove their limits, because once one Japanese carrier does something like this, they all have to follow suit or get left behind. I imagine that KDDI will be the first to announce the removal, followed by softbank. When Softbank finally announces, it will be accompanied by a huge amount of noise and BS.

Softbank iPhone 6 America Unlimited plan to provide inexpensive roaming

Updated with a correction on application requirements and some images.

Free calls to both Japan and the United States using Sprint's network.

No service application or service fee for plans over 5 GB.

I was planning on writing up a post comparing each of the Japanese carrier's iPhone 6 plans but that really gets tiring. They are all basically the same. As soon as one carrier outdoes the rest with some promotion, campaign, discount, offer, or other gimmick, the others quickly devising a similar scheme.

Thus, the answer to the question of which carrier is best for you shiny new iPhone is always the same: not you current carrier because

1. The discounts and cash back offered to people who port their number to a new carrier offset the early termination fee for leaving.
2. The new plans allow unlimited calling to all mobiles/land lines, so it no longer matters which carrier your friends and family use.
3. All carriers now have similar coverage across multiple high and low frequency bands.
4. All carriers now have similar issues with congestions and network slow downs.

However, this year is different. For American expats or people who frequently travel to the United States, SoftBank appears to be the clear winner in the iPhone 6 competition. After purchasing a majority stake in US carrier Sprint, SoftBank is now able to offer deals that Docomo and KDDI simply cannot match.

SoftBank "All You Can America" Plan

The full details are still scarce, but unless there is something profound that is being held back, the new US roaming plan from Softbank looks pretty nice.

• Roaming on Sprint's CDMA-2000 (3G) and TD-LTE ("4G") network (the latter will come sometime this (fiscal?) year)
• ¥980 per month only during months the service is used (free during the initial promotion period and).
• While in the US, voice, SMS, and data are available just as if you were in Japan
• Apparently unlimited calling in the US (according to tech blogs but there in no mention on SoftBank's press release)
• No need to apply for the service and no fee for people with data plans over 5 GB 

iPhone A1586 (iPhone 6) and A1524 (iPhone 6 Plus) frequency bands (SoftBank and Sprint bands)
CDMA EV-DO Rev. A and Rev. B (800, 1700/2100, 1900, 2100 MHz)
UMTS/HSPA+/DC-HSDPA (850, 900, 1700/2100, 1900, 2100 MHz)
TD-SCDMA 1900 (F), 2000 (A)
GSM/EDGE (850, 900, 1800, 1900 MHz)
FDD-LTE (Bands 1, 2, 3, 4, 5, 7, 8, 13, 17, 18, 19, 20, 25, 26, 28, 29)
TD-LTE (Bands 38, 39, 40, 41)

Only for the iPhone 6, for now

To do this requires the usage four separate technologies across multiple spectrum bands. SoftBank is a WCDMA carrier, but Sprint (like KDDI) is a CDMA-2000 carrier. While in Japan, the iPhone 6 would use SoftBank's WCDMA (1), FDD-LTE (2), and TD-LTE (3) networks. While in the US, it will use Sprint's CDMA-2000 (4) network, and (eventually), also their TD-LTE network. While some earlier iPhone models are technically compatible with Sprint, these will be excluded (presumably) because they are locked to the technology of the activation carrier. That is, an iPhone 5 activated on a WCDMA carrier can only ever be used with other WCDMA carriers. I guess that could be patched, but then that would remove the inducement to buy a new phone.

There are currently no other phones except for the iPhone 6 that support this combination of bands and technologies. SoftBank is considering releasing an Android phone that would also be compatible. An unlocked iPhone 6 will be ineligible for the all-you-can-america plan. It is also possible to expand usage to FDD-LTE bands 25 and 26 that Sprint is building out.

Coincidence or Planning?

The TD-LTE network that will provide the 4G data connection in the US was originally built out by Clearwire. Sprint at one point owned just over a 50% stake in Clearwire before scaling back to just under 50% in around 2011. Then after SoftBank CEO Son took control of Sprint and injected lots of cash, Sprint bought all the remaining Clearwire shares, obtaining a lot of spectrum and, by chance, a TD-LTE network, using the exact same frequency band (TD-LTE band 41, 2500 MHz) as SoftBank.

Makes me wonder how much that network figured into the decision.

NTT Docomo officially announces new pricing plan

Not long after making the previous post, the new data plans were officially announced. They will launch on Sunday June 1st, 2014. Orders for service will be taken from May 15. The new plans can be applied to both smartphones and feature phones. The data plans can be shared between up to 10 devices within a single family, and individuals can split their data plan between two devices.

If you are a single person who uses up 7GB of LTE data every month and does not make many phone calls, you won't see any benefit from these changes. 7GB would cost you ¥7,000, more than it does now. However, if 5GB is enough, you will see savings. If you make any out-of-network calls at all, you will also see savings.

Kakehoudai 「カケホーダ」Unlimited domestic calling

This excludes numbers that start with 0180 or 0570, etc. that incur separate charges.

• Smartphone: ¥2,700
• feature phone: ¥2,200

Pake-aeru 「パケあえる」Shared data plans

All the new data plans can be shared (分け合える). The single person plans may be shared between two devices, so you have a phone with a voice and data plan of 5 GB, and the 5 GB quota can be used on both your phone and a tablet. There is a ¥500 share fee for each shared device/person added, and each device is also subject to a separate ISP fee, so that's ¥800+tax for each additional device added. Additional data can be added at ¥1,000/1GB.

• Single person Data S Pack (データSパック): 2GB: ¥3,500
• Single person Data M Pack (データSパック): 5GB: ¥5,000
• Family Share Pack 10 (シェアパック10): 10GB: ¥9,500
• Family Share Pack 15 (シェアパック15): 15GB: ¥12,500
• Family Share Pack 20 (シェアパック20): 20GB: ¥16,000
• Family Share Pack 30 (シェアパック30): 30GB: ¥22,500

There are also business plans that go up to 3TB (3,000 GB) that can be split between 1,000 separate devices for only 190万円 (about $20,000US) per month. That's Serious Business. (Actually, it works out to 3GB for ¥1,900/month split over 1,000 SIM cards, which is actually a good deal if QoS is there.)

In addition, there are discount plans offered to long term customers. To qualify on the Data S Pack (2GB plan), you will need to have been a docomo user for 16 years. Your' reward: ¥600 monthly discount. With the 5GB plan, you get that after only 11 years (or ¥800 after 16). The share packs become eligible for discounts starting at ¥300 after 6 years.

VoLTE

Coming this summer according to the PDF attached with this announcement.

NTT Docomo to introduce price decrease, flat-rate voice, VoLTE from June?

There is no official statement from NTT Docomo about this. The story originated in the old fashioned print newspapers (as so many important stories do).

There are three particular facets to the rumored changes:

• A flat rate voice calling plan that includes all mobile and landlines for ¥2,700
• Total cost of LTE data and flat-rate voice of ¥5,900 (now it is about ¥8,000)
• A shared family data plan of 10GB for ¥10,000.

The current voice plan for Docomo LTE (Xi) contracts gives unlimited calling to other Docomo subscribers for about ¥2,000 per month (Talk 24 + base fee with 2-year contract). The out of network cost is HIGH: ¥42/minute (billed in 30 second intervals). This is so high, that over the nearly 30 months that I've had a Docomo Xi contract, I've placed an out-of-network call exactly ZERO times. I'll find a phone booth or fire up my SIP client and route the call through my United States VoIP provider before I'll pay that price.

Effects throughout industry (if true)

Of course the KDDI and Softbank would introduce completing plans. This is not an attempt to bring in new customers to Docomo, but the opposite – slow the flow of existing ones out.

This would also likely be good news for MVNO users. A bug in the Nexus 5 prevented it from working with 3G contracts, which forced many users of low-priced b-mobile SIMs to switch to LTE plans. While the wholesale pricing of 3G contracts allows for the inclusion of "free" minutes, this isn't the case with the pricing on LTE contracts – all calls cost ¥42/minute.

What makes this most ironic is that even with an LTE contract, calls are routed over 3G anyway because...

Voice over LTE

All Japanese carriers are planning on introducing Voice over LTE (VoLTE). There hasn't yet been a lot of talk about this, though. When it does come, it is expected to result in less expensive voice plans. Tsuda Hiromu at Engadget JP raises the possibility that this pricing is in anticipation of VoLTE introduction.

When you stop and think about it, that makes the most sense.

It's hard to see Docomo doing this if calls are still routed over 3G. So I guess this means we could see VoLTE from Docomo in June. If this does indeed signal the introduction of VoLTE in Japan, it would mean that KDDI and Softbank would be limited on their ability to compete on voice price until they too introduce VoLTE. This in turn means we'll probably be seeing more dumb promotions and unsustainable cash back offers from them until they get up to speed technology wise.

b-mobile "Free Data" SIM will lower cost of voice+data plans

Update: on sale now here: http://www.bmobile.ne.jp/fd/index.html.

Here are the details from b-mobile (which also describes their 3G voice-only SIM for feature phones) This will become my new recommended data plan for unlocked smartphones (not tablets) if you don't want to (or can't) hack your phone to fix the infamous signal bars and cell standby android bug. (yes, I call it a bug).

A modest price decrease on the low-speed data plan

The current low-cost LTE voice and data "smartphone" SIM from b-mobile runs about ¥2,000 per month for unlimited 150 kbps data. As with all Docomo LTE SIMs, there is no included call allowance. From November 23rd, the new plan will lower this to about ¥1,600 (1,560+tax). while increasing data speed to 200 kbps.

With the upcoming consumption tax increase, currently planned for several stages, b-mobile is no longer displaying prices with tax included. Be sure to confirm if prices include tax or not. Until now, almost all mobile-related prices were quoted with tax included.

This is about a ¥400 yen discount each month for an extra coffee at スタバ or a couple of mint crunkies (if they still exist). The change in data speed is insignificant – All of the low speed plans under about 400 kbps are really hard to use for anything other mail and chat. This SIM does support turbo charge options of 100 and 500 MB, good over 90 days, for ¥300 and ¥1,200.

The real savings

The price of the add-on, high-speed data plan has been roughly cut in half, from just under ¥3,000 to just over ¥1,500. Not only that, the new plan adds an additional gig of data for a total of 3GB per month. Previously, adding the larger data quota to the smartphone SIM would cost over ¥4,000/month. Now you can get a voice-capable SIM card with 3 GB of monthly, high-speed data, for only ¥3,120+tax.

Avoid the cell standby bug

Anyone who's been paying attention to the MVNO scene in Japan is well aware of Android's poor handling of Docomo data-only SIMs. A phone with one of these SIMs doesn't display signal bars, and the cell standby process kills the battery in a matter of hours. The fix requires rooting your phone and voiding the warranty.

People who didn't want to or couldn't do that had no choice but to buy a voice SIM.

Now, with the new price on the smartphone voice SIM with 3GB of data being at ¥3,120+tax, you can basically think of this as a data SIM with voice for free. The original prepaid 1 GB Flat Rate SIM, which is still available, cost ¥3,100/month (after the first month). For nearly the same monthly cost, you now get three times the data and won't have to void your warranty to make your phone work properly.

You could actually use this as a regular phone SIM, and make cellular calls, but the rate is not cheap and there is not in-network calling with MVNOs. None of the MVNOs have any room to get creative with voice plans due to Docomo's wholesale pricing. There are no packages offered, not even for Docomo subscribers. ¥40/minute is what you pay for voice with a Xi (LTE) plan and a docomo SIM. The FOMA (3G) plans are packaged such that MVNOs can include a free calling allowance, which is ironic as hell since VoLTE does not yet exist, so all voice calls, even with an LTE SIM, get routed over 3G.

It would be much less expensive to use VoIP or some sort of chat option for placing calls.

Plan details

• LTE
• Post paid (credit card)
• Limited to residents of Japan
• ¥3,000+tax upfront
• ¥1,560+tax base cost for 200 kbps unlimited data
• ¥1,560+tax additional (¥3,120 total) for 3GB of high-speed data
• Turbo charge (100 and 500 MB for ¥300 and ¥1,200)
• Calls: ¥20/30 seconds
• Normal, micro, and nano SIMs available

Nexus 5 is not compatible with 3G contracts

UPDATE: a bug report has been filed. This affects all 3G contracts, regardless of whether the SIM is LTE-capable or not. This Google Plus post has good discussion in the comments.

Reports in the comment section here and elsewhere widely indicate that, for reasons not exactly clear, the b-mobile 3G SIMs are not working with the Nexus 5. According to a local android developer, the phone does not even see the "NTT DOCOMO" network under available networks. While JCI has not yet tested the Nexus 5, they also have been getting a number of reports of 3G SIMs not working.

It his highly likely that ALL docomo MVNOs will be similarly affected.

This SIM will not work with the Nexus 5

SIM cards that are currently incompatible are the BLUE and white FOMA ones:

• Visitor SIM 1 GB and 14 day
• B-mobile FMC
• Talking SIM U300
• Amazon 3G smartphone
• Yodobashi 3G smartphone
• All the old, discontinued products that some of you still may be using (I still have the original 3G Fair), including:
• original 3G smartphone
• original Aeon 3G smartphone
• original talking 1GB flat rate
• original talking FAIR
• original 1GB flat rate (data-only)
• original FAIR
• original U300

If you are a user of a voice SIM, you can have your plan converted over to an LTE plan, but there are several disadvantages. First off, docomo's pricing for voice with an LTE plan is different than with a 3G plan. There is no option for an included number of minutes (free talking allowance), which is reflected in the lack of this option with docomo Xi voice plans. Second, docomo charges each MVNO a fee for both the issuance of a new SIM card and activation of a new account:

• ¥2,100 for a new account when switching from 3G to LTE
• ¥3,150 for a new SIM card.

According to their official twitter, new LTE products that may will have a different pricing structure for the voice plan will soon be available, but I don't have specifics. Also, it's unclear if the administrative fee of ¥2,100 would be generated again by the changing to a different LTE plan. I would think not, since as far as the docomo side of the equation is concerned, there is no new account activation – that should only occur when changing from a 3G to an LTE SIM.

Using the Nexus 5 with NTT Docomo Xi

UPDATE: See this post for a list of instructions on how to change your Docomo ISP to Mopera U from sp-mode, which is necessary to use the Nexus 5 (or any unlocked, non-docomo phone with a Xi contract). Users are reporting that there is not an option to add the cheaper lite plan online, but because the standard plan has a 6 month free campaign now, add the standard plan now, then within 6 months change to the lite plan by going to a Docomo Shop.

Nexus 5 home screens showing a connection to docomo LTE

There has been a lot of discussion and questions regarding exactly how to use the Nexus 5 with Docomo. Many of you have existing contracts for docomo LTE (Xi), and you may be wondering if you can just simply swap out the SIM card.

The answer is probably not.

If you just walked into a docomo shop and bought a Xi LTE phone, you are 99.9999999% using their "sp mode" ISP. However, the APN used with this ISP is filtered by the phone's IMEI number, with only numbers specifically whitelisted by docomo able to use this ISP.

Many of you may not even realize that Docomo has different ISPs, since the mobile carrier typically is the ISP. There was at one point a good reason for it, well sort of. Docomo used a separate ISP for data devices, like the old USB dongles or other devices that would tether a computer to their network. This did two things:

1. made it easy to charge a premium price for that service and
2. segregated devices that were potentially able to eat a huge chunk of instantaneous bandwidth from the typical customer.

Therefore, you will need to change your ISP from sp-mode to docomo's other ISP, Mopera U. sp-mode comes with extra services, like sp-mode mail that provides an @docomo.ne.jp email address. You will lose this email address with a Nexus 5. If you want to continue having an email address, you can continue having one @mopera, but honestly, with gmail, there is really no need for either an sp-mode or mopera mail account.

There are two basic choices of mopera plans:

1. Mopera U Standard for ¥500+tax includes email
2. Mopera U lite for ¥300+tax without mail

Sp-mode is a better value because it includes mail for the same price as the Mopera U lite plan, but しょうがない. Remember this is the just the charge to have an internet connection. You then need to have a data plan on top of that, and most people are using the Xi 7GB plan.

N5 using the mopera.net APN, which is preconfigured.

To change your ISP, I understand this can be done online through the my docomo page. If you can't figure out how to do that, you can just go to a docomo shop and get it done. You really don't need to tell them why you are doing it, and you don't even need to bring the phone.

NEVER change you ISP from sp-mode to mopera if you have an unrooted, unhacked, docomo Xi phone. Docomo firmware changes the APN when activating tethering, and this APN is incompatible with Mopera U. Data will work fine but you won't be able to tether. The Mopera U ISP and APN is only for unlocked, non-docomo phones.

Once you have changed the ISP to Mopera U, put your SIM card in the shiny new Nexus 5, then set mopera.net as the APN. It will most likely happen automatically. Alternatively, you can use open.mopera.net, which removes some filtering.

[List of docomo APNs.]

Here are some various screenshots from the mobile networks settings

This is the Non-North American version, and it can see  the other carrier's networks
In the case of KDDI, it is seeing their Band 1 LTE data network (voice not compatible)

070 prefix phone numbers for 3G+ phones

Starting November 1st, 2013, Japanese phone numbers beginning with "070" will be available for use with 3G, LTE, and 4G cellular phones.

070 is not a new prefix for Japanese cellular phones. It's actually an old prefix: it was (and still is) used for Japan's last remaining 2G cellular network, called "PHS" in Japanese.

However, with PHS usage in decline and 3G/LTE/4G phone numbers in the 080 and 090 space being rapidly depleted, they have opened up parts of the 070 prefix for non-2G/non-PHS use:

• If the first digit after the 070 is a five or six (ex. 070-5XXX-XXXX or 070-6YYY-YYYY), it is still a Japanese PHS number
• All other number combinations could be either a PHS number or a 3G (or more advanced protocol) number

One interesting interoperability issue: because PHS 2G is not compatible with worldwide 2G GSM, they cannot send or receive SMS text messages.

That's how Japan's mobile email system got started: it was invented as an alternative to SMS.

From a consumer's standpoint, Japan's mobile mail alternative to SMS was superior: it allowed very long messages, it could interoperate and send/receive from internet email addresses, and allowed for rich content much like HTML mail.

From a carrier's commercial viewpoint, mobile email was a blessing because carrier provided email addresses, unlike phone numbers, could not to transferred to rival's networks (via MNP procedures), locking in customer loyalty; subscribers are hesitant to defect to other carriers because they would have to change/lose their Japanese carrier mobile mail email address.

It is only a recent phenomenon were people in Japan have begun to use SMS, although usage lags compared to carrier email. This is because of a few factors:

• It is only recently that the government MIC mandated that carrier's SMS interoperate (send/receive SMS text messages between Japanese and international carriers)
• Japanese 3G phones often had the SMS/MMS functionality buried in a deep submenu and referred to by strange brand names ("C-Mail" for KDDI/au SMS and "S!Mail" for Softbank MMS). Foreign phone operating systems, such as Android and iPhone, tend to feature the SMS/MMS features more prominently in their user interfaces. As Android and iPhone became popular in Japan, awareness of this functionality increased.
• When the restrictions were lifted for SMS/MMS interoperability, internet services (both in Japan and overseas) started increasing the use of SMS as a verification method for Japanese customers.

Thus, sending SMS/MMS messages used to never work if sent to a 070 number. Now, people will need to know if the the 070 phone is PHS or not if they want to send an SMS.

PHS' popularity amongst the general public in Japan has dropped precipitously now that 3G is ubiquitous and even faster phones (LTE/4G) are available everywhere. However, there is one area where PHS is still used: corporations still use them for internal "employee assigned" phones as they're very cheap to buy and use in bulk with a corporate contract. They tend to be used as pagers, either connected to humans or machines.

When 3G was introduced, they first exclusively assigned the 080 prefix to the devices. They then eventually added the 090 prefix. During this time when 3G was new, some people were surprised to hear people tell them that their mobile number was "080", thinking that only "070" numbers were mobile numbers. Now, with the younger generation, some people may express surprise that somebody has a "070" number, as younger people associate the 070 prefix with old technology.

Both Nexus 5 models appear compatible in Japan

The Nexus 5 is now official. From the product page, select the "tech specs" in the drop down menu, then "View full tech specs". The "leaked" service manual appears to have been for the "Rest of the World model" (I'll call it international).

It is my understanding that Docomo's planned 150 Mbps LTE downlink will be using Band 3, which the international model supports, but not the North American model.

(Japanese frequency bands)

For people who are based in Japan but make trips to North America, the international model looks like the best route. You will NOT get LTE service in the US, but it is compatible with T-Mobile 3G (WCDMA Band 4) and AT&T 3G (WCDMA Band 2). We've all happily lived with 3G for years now. It is totally sufficient.

For people who are based in North America but make trips to Japan, the North American model is best. It is compatible with both T-Mobile and AT&Ts LTE networks (LTE Band 4), and also with what is currently the primary LTE band in Japan for Softbank and NTT Docomo (LTE Band 1). However, lacking Band 3 might become a hinderance in Japan using Docomo or MVNOs as Band 3 seems to be central to Docomo's expansion plans.

Supposedly leaked Nexus 5 service manual indicates support for Japanese LTE bands.

If this is really the Nexus 5 service manual, then this is good for Android users in Japan: Support for LTE without having to deal with a device that locks you out of mobile network settings.

FDD-LTE: Bands 1, 3, 5, 7, 8, 20.
WCDMA (HSDPA 3G): Bands 1, 2, 4, 5, 8

Band 1 is Docomo and Softbank's 2100 MHz, used for both LTE and 3G. As far as I can tell, the Nexus 5 does not support the low frequencies of either carrier, though.

CDMA is mentioned in the manual, but as you can see below, it is not listed as a "Supporting Standard". Therefore, my guess is that the reference to CDMA is probably just a standard copy-paste, to be read as "IF this did CDMA, here's what it would be."

However, as far as I can tell, CDMA is unsupported. (Also FeliCa, mobile Suica, etc. is not supported.)

NTT docomo does not prevent unbranded devices from connecting to LTE network

There are now several posts online that describe using the Nexus 7 LTE with various Japanese SIM cards. Unlike the iPhone (and just as I expected) there appear to be no problems getting a connection with an unlocked, unbranded device on docomo's "Xi" LTE network. LTE service, both direct from docomo and through an MNVO, works perfectly.

N7 APN settings (Image source).

Until now, we couldn't rule out a "server-side" origin for the problems that unlocked iPhone 5 users encounter when trying to connect to docomo LTE. This was because, except for those provided by docomo, there were no other LTE devices that supported docomo's primary LTE frequency (Band 1, 2100 MHz). We had two variables (iOS software and docomo servers), and one equation (Apple hardware), which is unsolvable.

We can now safely say that 3rd party devices are not subject to an across-the-board lock out from "Xi" LTE.

Prospects for unlocked iPhone 5S and 5C in Japan

It still remains unclear (due to lack of testing) what will happen when an unlocked iPhone 5S or 5C is brought to Japan. iOS is well known for disabling the ability to easily alter APN settings depending on the SIM card that is inserted. As mentioned in comments on another post, the iPhone Configuration Utility can be used to create configuration files that add new APNs, and this is used by some MVNOs to work around disabled APN settings. However, as I noted earlier, the docomo carrier bundle appears to prevent attaching to 3G and LTE networks with anything other than the sp-mode APN. If this is the case, it could render the configuration utility useless if these same rules are included on unlocked iPhones as well.

The sp-mode APN is filtered by IMEI number on the "server side." Only whitelisted devices (sold by docomo) can connect.

Nexus 7 LTE SIM options

The Shukan Ascii article compares different LTE SIMs in the Nexus 7. I'll briefly translate and summarize the contents in another post when I have more time.

In short, Docomo Xi SIMs work and are recommended by Shukan Ascii. You will need either:

1. a subscription to docomo's Mopera ISP (mopera.net APN) or
2. a contract with a docomo MNVO.

You cannot take a docomo SIM from a normal docomo LTE phone and put it in the Nexus 7. Most all docomo phones now use the sp-mode ISP. The Mopera ISP must be used.

A contract change was also required to get a KDDI SIM to work, but as I suspected, coverage is not the best (though better than expected in the Tokyo metro area). Emobile SIMs are not yet compatible pending a firmware update.

Shukan Ascii weren't able to get the Softbank LTE SIM to work with anything except regular 3G, but they admit they didn't try very hard. I know of at least one person claiming to have softbank LTE and an iPhone SIM card working with Android.

Nexus 7 LTE "currently" incompatible with emobile LTE

UPDATE: A firmware update will make the Nexus 7 compatible with emobile LTE.

From the Nexus 7 LTE purchase page, we have the following:

E-mobile band 3 (1800MHz) not currently supported.

I have no idea how to interpret the word "currently" in this sentence. It could mean that this current hardware revision is incompatible, and if you buy it, you'll never have the option of emobile LTE. Or, it could be that there is currently a firmware incompatibility that a future OS update will fix.

Nexus 7 LTE on sale in Japan

If you access the direct link for the LTE version on the play store, you can add the US version to your cart, and it indicates a 1-2 business days for shipping. However, on the official Japanese Nexus 7 site, it is currently listed as unavailable, though if you choose one of the other versions, you can change that for the LTE version (though the display language switches to English).

North America or European Version

Right now, only the US version is available from the play store in Japan. Both will work in Japan. Neither will grab the NTT Docomo's or KDDI's "800 MHz" bands. This is because there are a ton of bands that are called "800" (even "850" is sometimes called "800").

(Japanese frequency bands)

Docomo's "800" band is Band 19, and KDDI's is Band 18. The EU version supports Band 20, and there is not sufficient overlap on the downlink for this to support Docomo's low frequency (though the uplink does overlap). There is no overlap at all with KDDI at "800 MHz".

So, even though the EU version has "800 MHz" it won't have any benefit in Japan over the US version. This really won't matter at all for Docomo now because they don't seem to have deployed much LTE service on their "800 MHz" band.

North America: LTE Bands 1, 2, 3, 4, 5, 13, 17
Europe: LTE Bands 1, 2, 3, 4, 5, 7, 20

(To display the above information from the official Japanese Nexus 7 site, click 技術仕様, then スペック情報を表示)

Recommended to avoid KDDI

I stand by my earlier claim that the Nexus 7 will suck on KDDI for the immediate future. There are currently problems with Verizon in the US, another CDMA-2000 carrier, who just like KDDI, has rolled out an LTE network. However, the reason for the Verizon suckage is totally different from the reason why KDDI will suck.

[LTE is an evolution of W-CDMA which is in turn an evolution of GSM. CDMA-2000 is based on CDMA. W-CDMA and CDMA-2000 are both "3G" and they are totally different and incompatible technologies.]

Verizon has the proper network to support the Nexus 7, but they refuse to do so, citing the inability to activate a line of service for the device because it lacks a CDMA-2000 radio. If this is true, it's just temporary and mainly an excuse. At activation, the clerk fills out a form on a computer. There is a field for the CDMA radio ID, and if that field is blank, then the the form can't be submitted. Easy to fix — update the activation system.

There are two reasons to avoid KDDI with the Nexus 7 LTE:

1. No CDMA-2000 radio in the Nexus 7 LTE, so the device can't fallback to "3G" when LTE is unavailable, which will be...
2. All the damn time because KDDI's supported LTE network uses Band 1 (2100 MHz), and they recently got busted misrepresenting the coverage, stating Band 1 covered almost everyone when it in fact covered almost nobody at all.

Problem 1 above will remain until Problem 2 is fixed. I'm sure KDDI is building out the Band 1 network as fast as possible. The issue with Verizon just shows how difficult it can be to deal with a CDMA carrier, some of which don't even have RUIM cards.

Nexus 7 as an indicator of unlocked iPhone 5S/C performance with a Docomo Xi SIM

The iPhone 5 technically supported Docomo's Xi network (Band 1, 2100 MHz), but it never really worked. Using an unlocked device with a Docomo contract requires using Mopera as the ISP, as opposed to sp-mode. There has been speculation whether the problems with the Mopera APN were purposely caused by Docomo, Apple, or both.

I think there should be no problems with the iPhone 5S or 5C with a Docomo contract and Mopera as the ISP. I'd speculate that an Apple carrier.plist preference file was denying a connection to Xi with a Docomo (44010) SIM. I could be wrong.

If you can bring an unlocked Nexus 7 LTE to Docomo and use the Mopera ISP with no problems, then it shows that the Docomo is NOT actively preventing non-branded devices from accessing the Xi network.

A Docomo iPhone could FINALLY disrupt SIM locking in Japan

As far as I see it, the most interesting potential outcome of a Docomo iPhone is enhanced unlocking of phones between Japan's two large W-CDMA carriers, Softbank and Docomo. This will eventually encompass KDDI as Voice over LTE replaces 3G. (KDDI is currently immune to unlocking because they use an incompatible CDMA-2000 network for voice communications.)

Recap: The origins of SIM unlocking in Japan

SIM unlocking (as it's referred to in Japan) started several years ago, following Softbank Mobile's successful introduction of the iPhone 3G. NTT Docomo found itself on the defensive, for the first time ever, and you do have to sympathize just a little with the the arrogant bastards. Survey upon survey told them exactly what people wanted in a phone: mobile payments, water resistance, infrared, solar panels, one seg, pedometers, labyrinthine mazes of menu options, and an eyebrow plucker. The iPhone had none and this, Apple had no experience making phones, and Macs held a dismal share of the PC market in Japan.

And yet the iPhone quickly achieved unprecedented popularity in Japan, prompting Docomo to attempt to sidestep Apple by successfully pushing for the introduction of SIM unlocking guidelines.

(See our coverage of the debate, including an overview plus the opinions of Docomo and E-access, KDDI, and Softbank.)

"Guidelines" as set forth by the the Ministry of Infrastructure and Communications are just that - they are voluntary and not "requirements." However, in practice, telecommunications entities followed them. Up until now. Softbank simply refused to comply with the unlocking guidelines, even following contract completion (and even as they were buying back phones, unlocking them, and reselling them in emerging markets).

And so we fell into a stalemate.

KDDI and E-access (Emobile) are, for various reasons, not relevant to the SIM lock debate; it currently revolves around Docomo and Softbank. Softbank holds the coveted iPhone and no offering from Docomo has proved popular enough to make unlocking an issue to enough consumers. Here's why I think this will change if Docomo sells the iPhone.

Implications of an unlocked Docomo iPhone

Softbank phones are not compatible with the budget data and voice plans offered by MVNOs because Docomo provides the infrastructure. This means that only unlocked phones (or Docomo phones) are compatible. Several years ago, this would not have been an issue, but the MVNO space, led by Japan Communications Inc, has seen substantial growth.

(Comparison of all Japanese MVNOs.)

Many household names such as OCN, Panasonic, and Rakuten have entered the fray, lending legitimacy, in the eyes of the average (non-techy) consumer, to the notion of mobile phone service provided by an entity that is not an actual mobile phone carrier. This results in a higher intrinsic value for a device that works with Docomo versus one that does not (all other things being equal).

If NTT Docomo does indeed carry the iPhone, and if they continue with their tradition of unlocking all their devices, then this would create a large feature disparity between Japanese iPhone carriers. Any discrepancy in value is amplified by the fact that, once you wade through all the fuzzy math to arrive at the out-of-pocket cost of hardware and service, the total cost is almost always the same for similar devices across competing networks.

Recall that previous iPhone feature disparity, with respect to tethering and data caps, left Softbank on the brink of a customer revolt. This was narrowly averted by a yarimasho (aka executive order) from CEO Son. Softbank had no choice but to offer free tethering and ease data caps to match the value offered by KDDI. (Microsoft should have seen a similar reaction coming with the Xbox One versus the PS4.)

Unlocking phones is a slippery slope for carriers. I believe that NTT Docomo will, after making such a stink about unlocking and vowing to unlock all their phones, have no choice but to unlock any iPhone they may sell, just as they currently do for all Android device. If this creates a strong enough feature disparity, Softbank will be forced to follow, and they would lose any justification for keeping their Android devices locked.

win win.

LTE version of Google Nexus 7 will probably suck with KDDI, for now

UPDATE: KDDI has announced the sale of the wifi-only Nexus 7, and Engadget Japan has a more detailed article [J]. ¥39,800 for the 32 GB LTE model. Supported technologies and frequencies are:

4G LTE 700, 750, 850, 1700, 1900, 2100 MHz (Bands 1, 2, 4, 5, 13 17)
HSPA+ 850, 900, 1900, 2100, AWS (1700, 2100) MHz (Bands 1, 2, 4, 5, 8)
GSM 850, 900, 1700, 1900MHz

As suspected, it does not support CDMA-2000 and it does not support LTE Bands 11 and 18 (1500 and 800 MHz), which means that with KDDI, the only option will be Band 1 LTE, which in May had extremely limited coverage.

N7 LTE with KDDI?

A new post on Engadget is, without any citing any sources, announcing that the LTE version of the Nexus 7 will be available in Japan within a few weeks. Unlike iPads sold in Japan, it will of course be unlocked ("SIM free") for use with any carrier. According to Mat Smith at Engadget:

Google says it'll work on all three of Japan's major carriers (DoCoMo, Softbank and KDDI's au).

Technically that is true, because all operate a Band 1 LTE (2100 MHz) network. However, if you intend to actually have a good mobile experience, we recommend staying away from KDDI, for now.

KDDI lacks the appropriate LTE coverage

You may recall that back in May, KDDI was caught greatly exaggerating their Band 1 LTE coverage. They claimed over 95% coverage, when in fact they had less than 15% and no plans for expansion. While KDDI is certainly working to increase coverage, that's just an amazing misrepresentation. KDDI does have the stated LTE coverage with Bands 11 and 18 (1500 and 800 MHz), but unless the modestly-priced N7 has some uber multiband LTE radio, the only way to support all Japanese carriers is with Band 1, and KDDI doesn't have the coverage.

KDDI 3G is likely incompatible

If you use LTE in Japan and pay attention to the network displayed in the status or notification bar, you'll notice that it often falls back to "H" or "3G", indicating no LTE signal. The problem is that, unless the N7 LTE model includes a dual WCDMA/CDMA-2000 radio in addition to the LTE radio, there will be no fall back for KDDI users.

Instead, what will most likely happen right now is, anytime you would see an "H" or a "3G" icon with a SoftBank or docomo SIM, you'll see a BIG RED X or 圏外 (out of area) icon with KDDI.

Wait for clarification

Of course anything is possible. Yes, LTE coverage will improve with time, and yes, Apple makes LTE hardware that fully supports SoftBank (WCDMA) and KDDI (CDMA-2000). Therefore it's not impossible for the N7 to do the same. It is just highly unlikely to get that in a budget tablet priced between 30,000 and 40,000 yen. Even a Japan-specific model seems unlikely at that price, given the total increase in manufacturing costs.

It could be as long as a month before it's available if the Engadget article is correct. We'll be sure to keep you appraised of carrier options. As we've long said, an MVNO is perfect for a second, data-only device.

Sony Xperia A (SO-04E) Review

I have been using my Galaxy S2 (SC-02C) for about two years and although it has treated me well it has been showing its age. Docomo will not update it past Android 4.0.4 and even though 3rd party dev's have ported CM 10.1 to it I was looking to get a new phone.

When Google announced the Nexus4 I was very excited for a Japanese release since it was a good looking device and fairly inexpensive but my excitement turned to annoyance when despite there being a product page in Japanese a Japan release never came. Google IO came and went without any new release announcements and Docomo announced their summer line up so I decided to make a choice.

My number one choice would have been the HTC One, but AU is the only one who will be carrying that phone, so I narrowed my focus to the Samsung Galaxy S4 and the Sony Xperia A. The GS4 has better specs, a huge 5" 1080P screen and a modest battery. The Xperia A has slightly lower specs, a 4.6" 720P screen, and a waterproof case. I chose the Sony primarily because of the size and form factor, it fits much better in my hand and has much better ergonomics, plus the water-resistant case will really come in handy for those times I get caught in the rain while playing Ingress. My second consideration was that the smaller and lower resolution screen should be much more power efficient than a larger higher resolution one and I can't imagine you can tell much difference on such a small screen.

Specs

• Size: 10.5mm thick, 131mm wide, 67mm heigh
• Weight: 141g
• Continuous standby time: 3G: about 420 hours / LTE about 390 hours / GSM: about 360 hours
• Continuous talk time: 3G: about 630 minutes / GSM: about 570 minutes
• Charging time: About 160 minutes
• Battery Capacity: 2300mAh
• Display: 4.6 inches / Maximum simultaneous color depth 16,777,216 colors / Resolution 720×1280 
• Band/s: GSM850, GSM900,GSM1800,GSM1900, UMTS_BC1, UMTSBC5,UMTS_BC6, UMTS_BC19,LTE_BC1, LTE_BC19, LTE_BC21
• OS: Android 4.1 (Android 4.2 slated for July or August)
• Processor: APQ8064 1.5GHz (quad-core)
• Storage: 32GB
• RAM: 2GB
• NOTV, 1Seg, NFC / Felicia

Pros

• Water resistant
• Battery life
• Great ergonomics / form factor
• 13MP camera
• Sony TV integration
• Sony provides alternative applications and launchers
• Removable battery
• MicroSD card slot
• Playstation Mobile
• The best touchscreen keyboard I have ever used 
• Great build quality
• Loud speaker
• Native SIP support in the dialer

 Cons

• Not running the latest version of Android
• Docomo Pallet UI is terrible
• Water resistant port covers can be a pain to open
• The screen is a dust magnet 
• Locked bootloader
• Limited 3rd party dev support
• Microphone placement 

Software

The Xperia A ships with Android 4.1 and although this is not the latest version they have said that they will update to 4.2 sometime in July or August. Also unlike some Xperia devices this phone does not have an unlockable bootloader and since this is a Japanese variant of the Xperia ZR there will most likely be little to no 3rd party developer support. 

 I can't speak too much for the Docomo software because I went through and disabled or uninstalled as much of it as I could. (The feature in Android 4.0+ that allows disabling preinstalled system apps is intact, although some Docomo apps can't be disabled) The Sony software is actually quite nice though. They include their own keyboard, launcher, lock screen, gallery, camera, and music player. The launcher is much nicer than the Docomo Palet UI but I quickly switched to Nova launcher so that I could have a closer to stock look and feel. Sony has included both a Japanese (Pobox Touch) and international keyboard and I have to say that they are the best keyboards I have ever used, the international one includes swpe input features but the Japanese one doesn't.

I was very surprised and pleased to find that the dialer natively supports SIP accounts and the call quality over WIFI was very good.  I use this feature extensively for work so I was happy to find it included.

Hardware & Design

After using the Xperia A for about 1 week I can say that this is a great phone, I admit that it wasn't the phone I was waiting for but I am very happy to own it. It has a great form factor that sits well in your hand and is overall very aesthetically pleasing. My one complaint about the hardware design is that the microphone is on the bottom right corner of the phone, and I tend to place my pinky finger right over it when making calls. I will have to train myself not to put my finger there. This phone also has a notification light along the bottom that can change colors depending on what you are viewing on the screen or what type of notification it is alerting you to.

Screen

The screen is only 720P but it should use much less power than the 1080P screen on the Galaxy S4 and I think you would be hard pressed to tell the difference on such a small screen. I have noticed that when viewed at just the right light and angle that you can see some vertical lines on the screen that seem to be a side effect of the waterproofing, though you wouldn't notice it unless you are looking for it, and you can't even see it 99% of the time. The screen also tends to attract dust rather than fingerprints, the dust is easily wiped off though.

The built in light sensor is much better than the one on my Galaxy S2 and I rarely have trouble viewing the screen. There is also a backlight toggle that helps viewing in bright light situations. 

Camera

The phone comes with a 13MP camera and a dedicated hardware button that when held will launch the camera app even if the phone is locked. The camera takes excellent pictures in both low and bright light but the UI could use a little work. On more than one occasion I pressed the video record button rather than the button to take a picture. 

Battery

Once I disabled or removed as much of the Docomo bloatware I can say that this phone gets pretty good battery life and can easily last a whole day. With only email (Gmail and Exchange) and Google Hangouts set for push notifications the phone will use about 1% per hour when idle. I still have yet to completely run the battery down to 0%. I will probably pick up an extra battery pack for those Ingress heavy days but I am very happy with the performance so far.

Signal and GPS (GNSS Location based)

My last phone was the Samsung Galaxy S2 and I tended to get terrible reception and on at least half of my commute the data connection was unusable. The GPS on the Galaxy S2 was also hit or miss and used WIFI positioning pretty heavily.

The Xperia A uses Docomo's LTE network and I have found that I have LTE coverage around 75% of the time durring my day to day activities. While I still do have some dead spots on my commute the phone is able to recover from them much more quickly and actually displays when I have no connection rather than thinking it does and continually trying to send data when there is no connection. The only exception being when there has been a train delay and everyone is overwhelming the cell towers. 

This phone is a dual-constellation GPS/GLONASS device. GPS tends to be pretty spot on with very little GPS wander but I have not used it around really tall buildings downtown yet. According to Wikipedia "devices that can use GLONASS and GPS satellites together, provide greatly improved coverage in urban canyons and giving a very fast time to fix due to over 50 satellites being available. In indoor, urban canyon or mountainous areas, accuracy can be greatly improved over using GPS alone."

Buy, try, or no buy?

If you are looking for something that you can flash the latest ROM on and hack on you are probably better off going with the Galaxy S4 since its hardware is very similar to the international version and will have better 3rd party developer support. If you are looking for a water-resistant phone that has great hardware, removable battery, microSD card slot then you should consider this phone. 

If Google offered a Docomo variant of HTC One in the Google Play Store I would have a tough decision but if I had a choice between this and a Docomo compatible version of the Nexus4 I would have to say I would still choose the Xperia A.

KDDI advertising greatly misrepresented iPhone LTE coverage area

UPDATE: Nikkei article now online (in Japanese and behind a registration wall).
UPDATE 2: The government Consumers Affairs Agency has an official announcement here (PDF). All I can say is just WOW!

iPhone 5 75 Mbps LTE service [Band 1 (2100 MHz)] was extremely limited at launch. In addition, The stated plans for expansion to 96% was limited to the LTE bands used by Android smartphones [Bands 11 and 18 (1500 and 800 MHz)], and there were in fact no plans to expand iPhone LTE coverage. Thus, as of March 31, 2013, iPhone 5 75 Mbps coverage is at only 14% of the population.

対象役務の提供を開始した時点において、ｉＰｈｏｎｅ５を使用した場合に７５Ｍｂｐｓサービスを利用できる地域は極めて限られていた。また、前記アの表示をした時点において、平成２５年３月末日までに全国のほとんどの地域において７５Ｍｂｐｓサービスを提供する計画があったのは、Ａｎｄｒｏｉｄ搭載スマートフォンが送受信できる対象役務に係る電波の周波数帯域に限られており、ｉＰｈｏｎｅ５が送受信できる対象役務に係る電波の周波数帯域については、平成２５年３月末日までに全国のほとんどの地域において７５Ｍｂｐｓサービスを提供する計画はなかった。このため、平成２５年３月末日時点において、ｉＰｈｏｎｅ５を使用した場合に７５Ｍｂｐｓサービスを利用できる地域は、実人口カバー率１４パーセントの地域であった。

---

96% coverage including the iPhone by April 2013.

Back around the announcement of the iPhone 5, I recall being utterly amazed that AU by KDDI could build out their 2100 MHz (Band 1) LTE network from 0 to cover 96% in about half a year. Their existing network relied on 1500 and 800 MHz (Bands 11 and 18), which is what their other smartphones are using.

More on Japanese frequency bands.

I don't recall saying anything at the time, but I should have because it was indeed too good to be true. The 96% was the coverage percentage NOT for the iPhone network but for their OTHER networks.

The predicted coverage rate by April 2013 for KDDI's 2100 MHz iPhone LTE network was actually 14% at the time advertising was produced. The excuse I'm hearing is that the advertising team used the wrong information.

KDDI has better Band 1 LTE coverage in Tokyo than Softbank

Via Ishikawa Tsutsumu's twitter.

According to data put together by NTT Docomo, to show how much ahead they are with Band 1 (2100 MHz) LTE deployment, KDDI actually has a larger number of base stations in the 23 Ward area of Tokyo than Softbank. It is of course no surprise that Xi would have the largest number of stations, since Docomo was the first to deploy LTE.

Band 1 is the main band in Japan and the frequency that the iPhone supports.

KDDI is actually in a very good position to cover Tokyo for phones that support 800 MHz LTE, which I assume KDDI will be releasing in the future. This will provide great coverage below ground.

iPhone LTE data with a Docomo nano SIM

Via commenter Willy comes a post purporting to have LTE data working on an iPhone using Docomo's Xi network. The post is in Japanese, so I'll explain below in English. It seems he:

1. Started a contract for Xi with a Docomo nanoSiM (aka nanoUIM) with an factory unlocked iPhone.
2. Turned on data roaming (Not sure why - maybe because DCM is not in carrier.plist?).
3. Set the APN to open.mopera.net.
4. Used iTunes to restore the 6.0.1 firmware, downloadable from here:
   http://appldnld.apple.com/iOS6/041-8531.20121101.Fvjr6/iPhone5,2_6.0.1_10A525_Restore.ipsw

His carrier version is 13.0. He confirmed that power cycling the phone, yanking (and replacing) the SIM, and turning off roaming didn't affect the ability to connect to LTE. Turning off automatic carrier selection shuts off data, however.

If this works for a Docomo SIM, it should work for a b-mobile SIM. I don't have any idea why simply restoring the firmware would work. As always, do any of this sort of thing at your own risk!