---Full disclosure: I am an AT&T customer and have paid out the nose for using their International Plan, which in terms of data capacity would be generous in 1995 on a WinCE device. Everything else mentioned here, data connection related, is an unknown for me, and plan on evaluating them once in Japan this March.
Full FULL disclosure: If anyone wants to sponsor any or all of my trip this year, I will happily provide them with their choice of either
- A fair and balanced review of what ever they're selling
- Or 4 bags of different flavors of KitKats
Cellphone coverage is not the critical issue (for most people) travelling in Japan, it's high speed data. For my trip in 2015, I relied on AT&T's international plan, and in 2016 I bought some NTT DOCOMO SIMs off of Ebay. You can read more details here, but in the end we swapped our AT&T SIMs back into our phones, and forked over another chunk of change on the next month's phone bill. Note: If you have a good data connection, Line is great for group chatting and voice calls; so TOTALLY endorsing Line, but sadly not getting compensated. For international calling use Google Voice (Android or iPhone) but wouldn't work on data, had to be on WiFi.
Part of AT&T's "international plan" includes a hot spot finder, which in theory, let's you find and connect to partner WiFi hot spots. It's free and worth every penny. Actually no, I retract that: we overpaid for the app. When it did guide us to a working WiFi, either we connected and had no internet or we were presented with a login page in our browser asking for credentials we did not have. And you had to leave it running in the background eating up our batteries. AT&T reps insisted we should not be having any issues or need to login to any sites.
This year will be different (I hope) by using a Pocket WiFi (MiFi), which is essentially a data-only cell device that you connect your phone/laptop/tablet to via WiFi and use it as a modem. I'm going to use Global Advanced, which is NOT an endorsement of any kind, but I'll certainly praise or complain about it as appropriate when I return. The idea is sound and the price is not outrageous, there are different tiers of connection speed, and you can find cheaper competitors. I spent multiple hours shopping, comparing and mulling things over. Your needs and choice will be determined by budget, bandwidth needs and locale (staying in big cities, or travelling around the country side.) I went with the fastest device available as I will be sharing the data pipe with my college student sons.
There are a couple of other things I want to try while I'm in Japan, both claim free WiFi by allowing you to connect to partner hot spots similar to AT&T's broken promise. The first is NTTBP's Japan Connected - Fee WiFi app. There is also the NTT East "Flets" free WiFi, which appears to be a program for tourists to get a password that works for 14 days and uses either your browser or the previously mentioned Japan Connected app. The instructions, well, thorough might be a good word, we'll see. Confusing might be the other word.
Stay tuned....
Update post Japan....
When I went to add the International Plans on my AT&T lines I discovered they improved the offerings, now with International Day Pass; for $10/day/line we keep our current domestic plan overseas. Verizon has something similar.
It’s a pay-if-used plan, so any bytes or calls would charge me $10 for the entire day. With three lines we could have saved about $110 using the Pocket WiFi instead of mobile data/phone; however if any of us incurred charges with data or calls we’d end up much worse off. So cancelled the Pocket WiFi.
That being said, our phones worked, data worked generally well, there remain some odd dropouts on all our phones. Seems to be something to do with roaming, not the partner provider (NTT DOCOMO).