1, Because this watch can only support 2G internet. So the function which needs internet may not easy to use.
2, There is no APK for IOS phone, so five functions can’t sync with IOS phone (1. Anti-lost, 2. Message reminder, 3. Notifier, 4. Remote Camera, 3. Bluetooth music), but all other function can be use normally like function which do not need apk and Bluetooth phone call sync.
Android Phone can support all function in the description.