Is it eth wallet compatible only ?
If u are looking for mass adoption, can Eth blockchain process large volume of transaction quickly enough ?
Cause if not, who is taking the risk of purchase without unsufficient funds on the eth wallet ?

Imo, it would make proxy tokens more valuable  to force prxy conversion and more simple for enduser (shall i change fiat for eth or prxy  )

Last, but not the least, how do u deal with fiat/eth or prxy variations for merchant to handle what they charge.
Let's say i'm an ice cream merchant, i won't check prxy or eth price every minute. What i do know is that
i wanna charge 3 euros for that ice cream. can i enter a fiat amount in the app ?

gl for ur project