Thank you! I had gamepads working on my PC build just fine so did not know why it didn't work. When I connect the MFi controller to my iPhone now it registers as gamepad 1. You have the following note regarding Android but I suspect it may hold true for iOS as well.
"Be aware that on Android you may find that the first gamepad connected is actually placed in slot 1, as the OS reserves slot 0 for general bluetooth connections."