In China, nearly everything works via the same app (WeChat) and via QR code. Every grocery store, coffee shop, train station, or point of sale has the same scanner, where you can flash your QR code. I don't think I saw a single physical currency exchanged in the entire 6 weeks I was there.

I keep hearing that X wants to be the "everything" app. WeChat is _already_ the everything app. It's DoorDash, Venmo, Facebook, Instagram, and about 500 other apps in one.

I will say that I disliked the pattern of every restaurant using a WeChat "mini app" where it basically loads an entirely new app within WeChat just to see the menu or order. It felt much clunkier than just using a web page.