I've seen groceries that use either cart-bound computers, hand held scanners, or phone apps for check out as you shop systems. The latter two are kind of a wash

I've seen groceries that use either cart-bound computers, hand held scanners, or phone apps for check out as you shop systems. The latter two are kind of a wash when it comes to convenience, as you trade time at the till for time when you pick an item up and decide to put it in your cart or not, but the cart bound computer used RFID, and would automatically update as you added and removed items. Of course there's also things like Amazon's system, where you literally just walk in and out. Which is a lot tech heavier, but a lot more convenient too