This is the minimal guide for installing LineageOS 17.1 on OnePlus 3T abtracted from LineageOS offical guide. It works at the time of writing so no gurantee for further updates.
- Enable OEM unlocking and USB debugging on your phone with developer mode.
- Download latest Android platform tools for Windows, for Linux, or for macOS from Google. The full guide can be found at Using ADB and fastboot.
- Connect your phone into your computer with USB mode.
- Install the built-in OnePlus USB Drivers or use UniversalAdbDriver.
cdto the platform-tools directory, runadb devicesto see if your phone is connected.- Run
adb reboot bootloaderto boot your phone into bootloader mode. - Run
fastboot deviceswhile in bootloader mode to see if your computer still connects to it. - Run
fastboot oem unlock. Your phone should be reset and reboot automatically. - Setup your phone. Then re-enable USB debugging.
- Download latest custom recovery from TWRP.
- Run
adb reboot bootloaderto boot your phone into bootloader mode. Also make sure your phone can be find in fastboot mode by re-typingfastboot devices. - Run
fastboot flash twrp-3.4.0-0-oneplus3.imgto flash custom recovery. - Run
fastboot boot twrp-3.4.0-0-oneplus3.imgto boot into new recovery mode. - Download the LineageOS installation package.
- Download Google Apps using the
arm64architecture. Choose the packages you prefer (I recommendnanopackage). - In recovery mode, tap Swipe – Format Data
- Return to the previous menu and tap Advanced Wipe, then select the Cache and System partitions and then Swipe to Wipe.
- Sideload the LineageOS and Google Apps packages:
- On your phone, tap Advanced – ADB Sideload, then swipe to begin sideload
- On your computer, sideload the package using
adb sideload lineage-17.1-20201026-nightly-oneplus3-signed.zip. - Then sideload the Google Apps using
adb sideload open_gapps-arm64-10.0-nano-20201031.zip.
- Back to recovery main menu. Reboot your device.
- Setup your LineageOS.