Not a reliable source of payment
The app is not at all intuitive. It’s easy to download and add a card when abroad. But using it is a different matter. I managed to pay in one shop - but basically had to give my phone to the retailer (who also didn’t have much of a clue). She managed to scan me. Then I tried to pay a taxi driver and it didn’t work - he couldn’t scan me and when I tried to scan him, it said I had to add a card (already done abroad), but wouldn’t let me add any of visa, mc or Amex. Ended up having to get the police involved to allow me to find an ATM to withdraw cash. Basically it’s not a reliable source of payment at all. But neither is paying by card (for taxis). Uber equivalent app requires a local phone number to register. So carry cash!