As a Roblox user, whenever redeeming Roblox toys or gift cards, I find it extremely annoying and time wasting typing in 10-13 digit numbers and sometimes having to retype it.
I believe a feature for the roblox website and app such as being able to hold up the toy code or gift card code to your devices camera to redeem that code would cut down on time and would overall provide a fun experience for users redeeming codes such as avatar items and gift cards.
Ex : App stores iTunes gift card has a scan to redeem feature.