Having discovered Curve a few days ago, I installed 2.1.10 from the Play store, and having tried adding a card, it was declined by the app, despite having sufficient funds. On launching the app again, it hung on the logo screen, as per this user’s post:
If I delete the app’s data and cache, it takes me back to the “add card” screen, tells me the card’s already added, then hangs again. Rebooting the phone makes no difference. Samsung Galaxy S9+ on Three, running Android 9. As such, your service is unusable.
Edits 14/02/19, 15/02/19: The updates still don’t work.