While OnePlus 6 root method works fine as it is, TWRP officially released their official version of TWRP, which makes rooting the OnePlus 6 slightly easier as now TWRP recovery can be easily booted using the command, “fastboot boot TWRP”. Now, you can also install TWRP recovery permanently with the TWRP installer ZIP file but I do not recommend it as it has a bug where the user may end up in a bootloop.
For those of you who have installed a new custom ROM and wanted to change to another ROM, you will probably have noticed that most custom ROMs now included CyanogenMod recovery, which overwrites your existing TWRP recovery (that you probably installed while rooting). Well, to install TWRP permanently after installing a custom ROM, you simply need to flash TWRP recovery ZIP after installing the ROM. That way, you can install new ROMs in the future without having to re-install TWRP recovery using your computer.
Nandroid backup is the process of backing up every single thing inside your Android phone/tablet includingMessages Call Settings Apps + App Data IMEI Why is it important to have a Nandroid Backup?