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)