There are a million apps that you can download, but there are a couple that are must-haves. One gives you the train times and stations in English and the other is Google Translate. If you search the app stores you can find a lot of others including ones that will teach you some handy phrases. Others that will translate your voice to Japanese text.
Google Translate App
I only discovered Google Translate app on my last trip, and it’s a game changer. Obviously I’ve used the website to translate text online, but this is different. You can use the camera on your phone and hold it up to a sign in Japanese and the camera will scan it and translate the text. It’s not perfect, but it will get you what you need to know and it’s better than anything else. I’m assuming they will continue to improve it.
FYI if you can read Japanese you’ll note the pictures aren’t an exact translation. The screens changed between the time I took the screenshots, but it should give you a good idea of how things work.
There are probably quite a few train apps out there, but I downloaded this first many years ago and haven’t really tried anything else. You can use it as app or you can go to their website. If you’re using the Japan Rail Pass there is an option to only show those trains. That’s a huge convenience.
You can type in the name of the stations, or if you want to see what the nearest station is the app will use GPS to find your location. The results screen is a bit cluttered but you get used to it pretty quickly.
LINE is the #1 chat program used by Japanese people. It’s mostly a chat program like any other. You can send texts, pictures, make free calls, etc. When I rented my AirBnB we communicated by line before the check-in. If you have a Japanese person you need to communicate with, it’s a sure thing they’ve heard of LINE and there’s a very good chance they have it.