How to Add Multi User Support to any Android Device with a Build.Prop Mod
One of the redeeming features to many about the OEM software on Samsung and LG devices are their overwhelming amount of useful features. Yet it seems Samsung, as well as T-Mobile LG devices, have inexplicably removed a pretty useful stock Android feature – multi user.
Multi user is useful as it allows you to share a phone with someone you know, like having separate user accounts on a computer. The feature is built into stock Android and you’ll find it on any Google device along with most phones from Huawei or LG will have it, yet for some reason, Samsung (and T-Mobile LG devices) have removed it.
But you can actually re-enable it, using an old, well-known modification to the build.prop system file that was recently suggested by XDA Senior-Member Christoph21x. In order to do so, you will need root access via Magisk or SuperSU.
Add Multi User Support on any Android Device
Firstly, install an application that can modify your build.prop file. I recommend Build.prop editor.
Now, open the app, grant superuser access and scroll to the bottom and add the following two lines.
Now save the file and reboot!
You should now be able to add users by pulling down the notification shade all the way down to the expanded toggles. The top right should have the multi user option. You can then hold the power button to switch users, as the power menu will be expanded to fit this new option.
How this works is that we are modifying a system property value which is defined by the UserManager.java file in AOSP. UserManager reads these property values from the build.prop file at boot, so by modifying the properties we can re-enable this feature even though certain devices have disabled it.
This is one of those rare cases where a build.prop modification actually works. You’ll find many, many suggested modifications to the build.prop file that promise to make your phone faster, but the reality is that most modifications do absolutely nothing. This is because OEMs modify the software a lot, and without the source code we have no way of knowing which build.prop edits will actually work without trial and error.