You raise an interesting point here. To use digital Suica/PASMO/whatever in Japan, your mobile phone needs to have NFC hardware called (Sony) "FeliCa (Osaifu-Keitai)". Few Android phones sold outside of Japan have this hardware. However, Apple is a bit special -- I think all modern iPhones sold globally support it. (Please correct me if wrong.)

Google also tells me:

    > Samsung confirmed it's working with JR East to bring Suica and FeliCa support to Galaxy phones sold outside Japan starting in 2027.

I found that out before I went, so I took an iPhone specifically for the job. The ease is gives you makes it worth carrying. As for northeast of Tokyo, very few visitors do that, sadly.