Which APP do you use?
To control the mBot Ranger with mobile devices, you can use the Makeblock APP or mBlock APP.
For the above two APP, they required system below on mobile devices:
iOS: iPhone4S/iPad 3, iOS 9.0 and above
Android: Android 4.3 and above
Among your devices, I think the IPad 2 won’t work. But for the issue “incompatible device” happens on the other two devices, please make sure you are using the correct APP.
Once still the same issue when using Makeblock or mBlock APP, please reset default program for mBot Ranger have a try.