The smartwatch is compatible with Android 5.0 or higher/iOS 9.0 and higher devices. All devices should support Bluetooth 4.0.
No, you cannot change the strap.
Watch receives phone calls notification under Bluetooth connection. With the inserted sim card, it can make phone calls.
It can operate only with the sim card.
Yes, with 200W camera.
No, you can’t.
All functions of the watch can be used. Such as sync motion data, remote control, find devices, data sharing, etc.