When using the subway to move around Tokyo, Osaka, and Kyoto, do I need to purchase a subway pass or can I just scan my Suica card from my iPhone? Thank you for your help 
.
You can just use suica, but I think if you’re going to be using the Metro a lot it’s better to buy a pass. A 3 day pass is very economical in Tokyo and it goes everywhere. It’s harder to get around in Kyoto via Subway because it’s not as extensive as larger cities and several other train lines run the routes you’ll probably want.
Thank you for the advice!
What are the main things we would use our Suica card for?