I'm looking for a constant identifier from an android device whether it's phone or tablet or some other. I checked and found 4 options IMEI, IMSI, Android_ID and MAC ID. The first 3 are found not reliable as they can be changed in one or other method.
So can we trust MAC ID of the device considering the device has any sort of network in it, whether it's bluetooth or wifi, can it be changed?
Also will 2 devices have same MAC ID ?
OR can i make a unique id from all the above. Please suggest me a method to get a unique identifier from an android device. I need to to recognize all the users of my app.