Unfortunately OBDEleven has stopped working

I have now tried 3 different old Android devices with my OBDEleven NextGen but all of them have resulted in “Unfortunately OBDEleven has stopped working” when I try to connect. I can connect to the OBDEleven dongle with an IOS device so I know it is working but, of course, only some of the functions are available on IOS. The Android devices have ranged from Android 4.4 to Android 9, all with the same result. I have tethered each one to my iPhone so that they have an internet connection. I wondered if I would have a different result if I put a SIM card in the device instead of tethering. 

Is anyone able to advise why I always get the same message and, more importantly, tell me how to make it work? I would even buy a cheap Android device if someone can recommend one that will definitely work. 
 

Thank you for your help.

Dave