So, if you go to Japan, don't make the same mistake I did and count on free Wi-Fi: get this Japanese portable Wi-Fi https://www.mobal.com/pocket-wifi-japan/ from Mobal in advance. Out of habit, I decided, "Oh well, I'll buy a SIM card when I get there"... Yeah, right. I spent half a day running around looking for one, and the settings were all weird. Finally, I bought this router, and it turns out there's no problem at all. You put it in your pocket, it works all day, and you don't even notice. And here's the funny thing: at first, I thought it was an "unnecessary thing," but in the end, you can't even properly access the map without it—there are all these subway stations there, you'd get confused in no time.