Install Android 4 2 Camera, Gallery APK Apps ICS And Jellybean ROM Android 4.0.4 & 4.1.1, Download
. It has been explained very well so that you can understand well. Check the latest version MiUI stock camera from the developer page.The Mi A3 is a stock Android or Android One phone from Xiaomi available at cheap cost.Don't confuse custom ROMs with rooting - they're completely different.It will definitely remind you of Resurrection Remix