[Lammy]

Do I misunderstand what Ubuntu Touch is? I thought it was its own thing whose only relation to Android was the BSP, not some type of layer on top of Android. If so then it seems irrelevant and unfair to bring up w/r/t the well-tested Android-to-different-Android path.

[saidinesh5]

Unless your phone has full mainline kernel support (pinephone, librem 5, pocophone f1 etc...), All these Linux on phone projects mostly use Android system services (init, surfaceflinger, rild etc..) to talk to the device hardware, without bringing up the Android UI.

They do this so that they don't have to reverse engineer and write the hardware drivers from scratch and simply use Android's user space drivers for them.

I haven't been involved in that domain for a while, but it basically meant reusing the contents of your device's /system and /vendor partitions and simply installing the Linux OS into /data.