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I have a Samsung Galaxy E5 phone it has Operating System Android 5. I want to upgrade it to Android 10 (root/unroot) replace ROM whatever method. I am looking for a systematic guide to do so.
I also have a Micromax E311 phone with OS as Android version 4.4.2 I want it to be upgraded to Android 9 or whatever possible.
I have a Sony Xperia XA ultra having OS Android 7. I want it to upgrade to Android 9 or latest.
I have an HTC 728G having OS Android 5 I want to update to latest Android 10 or whatever it is.
Is it possible to do OS upgrades in these phones. If yes please guide me how to do so I have never done before all phones I have used extensively I don't mind If I loose them or corrupt them in my experiments.
Also these phones except Sony Xperia don't have a VoLTE(Voice over LTE) support is it possible to somehow upgrade the hardware to have VoLTE support.