You jest, but an actual "digital wallet" device is something I'd quite like to see. Something that's actually secure (like not running an ancient android version that never sees security updates). That only deals with money, without any garbage running on it. That displays and verifies the amount before processing any contactless payments. That supports multiple banks, multiple bank accounts, multiple payment cards etc.

I utterly detest the idea of having to use a phone for anything that I'd like to be secure. I browse Reddig on that thing. I watch porn on that thing, I don't want my porn anywhere near my bank account.