I am pretty sure scanning the gift card barcode with your phone only works for Mobile order (for food) and shop in store mobile checkout (for merchandise). When I bought
Genie+ in May I could use a saved Credit Card or manually type in a gift card, but could not scan a gift card. It is kind of mind boggling that it is the same exact app but tie payment process doesn't work the same way.
I do like the gift cards with a barcode because of the ability to scan in the app. I've also found that more often now when CMs see your gift card has a barcode they offer to scan it too which I prefer over swiping as the magnetic strip seems to get de-magnetized sometimes.