eID is the obvious answer here in Europe. Right now it's kinda scattered with different providers, but I believe EU is working on a more universal protocol. Unfortnately there are rumors it will require official Google/Apple play stores, unrooted devices, and all that it does today already.

But it should be treated as a relatively safe ID, it's even used for voting. If you feel uncomfortable, just have one device for eID, and one for everything else.

I think it's a great tool if we want to implement some sort of liquid democracy feature.