Wifi Availability in Tokyo and Japan

Public, free wifi isn't great in Japan. A few places, like train stations or tourist offices, have it, but it's much less prevalent than in many other countries.

Accommodation in Japan usually does have free Wifi though - if you'll be staying at hostels or business hotels, say, you'll almost certainly have free Wifi there. Some shops/restaurants/coffee shops often have Wifi as well - Starbucks, McDonald's, many convenience stores. These options often have restrictions though (maximum 1 hour, say), and you'll sometimes have to sign up in some way in order to use them. Or sometimes you'll need Japanese language skills.

How much surfing do you need to do in Japan? If you're content with doing your interneting in the evening, at your hotel, you should be fine. If you want constant access during the day, you'll struggle.

I guess the main reason I'd be using it is for maps like google maps, just so I can navigate myself around. Not really concerned with just surfing the internet

Wifi hotspots are definitely not going to be adequate to get you map data "on the fly", when you need it. Suggest you download the maps for the areas you want so they can be used in offline mode. Then your map app should function fine without a "live" wifi connection.

I find free wifi to be fairly prevalent in Tokyo. Many JR stations have it. Many Tokyo Metro stations have it. Many stores have it. Starbucks has it. McDonalds has it.

But there's no reason not to get data of your own. Data sims are cheap for Japan. Cheaper still if you buy them before you get to Japan. $20-$30 will get you data while you are there as long as you have an unlocked phone.

Suggest you download the maps for the areas you want so they can be used in offline mode.

No can do. Japan is "special". There must be a copyright agreement in Japan that prohibits maps from being downloaded. Google maps will not allow you to download maps for Japan. Here maps doesn't have a downloadable map for Japan. You have to use the mapping apps live. You can use android apps that use openmaps to get an offline map of Japan but openmaps is not the best map. The big problem is that much of the writing will be localized so unless you can read Kanji, it'll be hard to find or search for things.

The tourist offices in Tokyo, Kyoto, and Hiroshima give out excellent tourist maps of the cities. They're not perfect - they're mostly aimed at the main tourist neighborhoods, obviously - but they're certainly enough to get you around.

I've downloaded both maps.me and and OsmAnd maps so hopefully these should give me a good idea of getting around.

During my first visits to Japan, I had a separate Japanese SIM card (data only) in a second phone to ensure that I could have data on the go.

I found: (1) almost all the AirBnBs I stayed at had pocket wi-fi's; and (2) there's decent [growing?] public wi-fi.

Thus, I don't use the Japanese SIM card anymore.

I have found some of the recent AirBnBs I've stayed at don't have pocket wi-fi. Thus, it can be a good idea to ask in advance.

On my 7" tablet if I open google maps for an area and zoom in when on wifi, I find this bit of the map stays in memory/cache even when off wifi. I can't do all the clever google map search type stuff without wifi, but I can use the map. My GPS locates on it as well.

I used this method for cycle touring over tens of kms, so if you only want a small urban area you will be fine.

Do not clear your cache as this will delete all your stored maps.

Even now, I can still see in detail maps of where I was over a month ago.

A further tip. Seven 11 convenience stores have some sort of public wifi. Even without logging on, I could open google maps and get located. Just find one and stand outside.