MAKE SURE APP RINGS HOME EVERY TIME IT OPENS TO SEE IF THERE IS
ANY URGENT MESSAGES I'D LIKE TO TELL ALL MY USERS.
I don't care the slightest if it's something Apple doesn't want you to do, or wants you to do over notification center, just do yourself a favor and create a direct channel between yourself and the customers (so that you can send them a message whenever you felt like).If you had such channel, you could've told them (after an apology for the inconvenience it's caused) how to remove bills, and that you're working on the next version, and the buy button was a bug, and avoid 1-2 star reviews, and sell much much more (no one buys/download a 1.5 star app).