That is quite a strange symptom, especially if it’s working well with the Android device. I can think of two possibilities:
1. The iOS device is saving some kind of pairing information for the meter that it shouldn’t be. If you go to settings->bluetooth and see the Mooshimeter listed even when it’s not connected, delete the pairing information by pressing the little “i” next to the Mooshimeter’s listing and hitting “forget device”. Then try again.
2. It may be that the Android device is never disconnecting from the meter even when it says that it is. If it’s in the room when you are trying to do the iOS connection, is it possible to turn it off and try again?
Let me know how it goes, best