I was in line at 7-11 at my university, where an girl was trying to use the currentc app. She was 2 people ahead of me, when I went up to pay she was still trying to pay with the app. At first her screen was to dim, and the scanner would not read the QR code. Eventually she was able to pay, but I was already long gone by that time. If you look on the google play store it has a rating of 1.1 starts.
This is straight from its website,"Merchant Customer Exchange is the only merchant-owned mobile commerce network built to streamline the customer shopping experience across all major retail verticals."
With an app that rates 1.1 stars and no improvement, I don't think it cares about the shopping experience, and people will see this eventually.