Thanks. I will definitely be renting a pocket wi-fi to have service while we're there, so Google Maps will probably get a lot of use. I am also going to download one of the transit apps mentioned up-thread - I think I need to do what
@Haley R did and download them both to decide which I like better.
I've heard good things about the English abilities of a lot of public-facing workers in touristy places, but we also have some basic ability to communicate in Japanese. Mine is conversational at best, but my daughter has had two years of high school Japanese, eight weeks of living there, and by the time we leave, probably another year of college-level classes. So I'm not too terribly worried about communication except in some of the more rural places we're visiting.