Reading through the now locked Genius Go Discussion thread, there was feedback back in July about issues with iOS7. Here we are nearly 4 months later, and its still unresolved.
The app is pretty much broken on iOS7. I have managed to answer two calls out of about 20 in the last few weeks. Even more annoying when it misses a call, the phone number is not in the 'recents' call list, so I cant even try to call people back via GSM.
It used to work 'alright' in iOS6, but that ship has sailed, and it is impossible to go back to iOS6, so please fix the app for iOS7.