Installation ============ .. contents:: :local: Download Dumbdroid ------------------ Warning: Dumbdroid is under active development, and comes with bugs and missing features. Use at your own risk! Builds updated on October 14, 2025. Make sure to unpack first! ================= ============ ============================ Dumbdroid variant Qin F21 Pro Doov R77 Pro, Qin F22 Pro ================= ============ ============================ Google apps `gapps30`_ `gapps31`_ Vanilla (microg) `vanilla30`_ `vanilla31`_ ================= ============ ============================ .. _`gapps30`: https://dumbdroid.eu/ota/stable/lineage-21.0-20251014-UNOFFICIAL-dumb_gapps30-signed.img.gz .. _`gapps31`: https://dumbdroid.eu/ota/stable/lineage-21.0-20251014-UNOFFICIAL-dumb_gapps31-signed.img.gz .. _`vanilla30`: https://dumbdroid.eu/ota/stable/lineage-21.0-20251014-UNOFFICIAL-dumb_vanilla30-signed.img.gz .. _`vanilla31`: https://dumbdroid.eu/ota/stable/lineage-21.0-20251014-UNOFFICIAL-dumb_vanilla31-signed.img.gz Necessary tools --------------- * mtkclient_ * `fastboot and ADB`_ .. _mtkclient: https://github.com/bkerler/mtkclient .. _fastboot and ADB: https://dl.google.com/android/repository/platform-tools-latest-windows.zip Unlock the bootloader --------------------- This will factory reset your phone! Open Settings->About phone. Tap on "Build Number" until you unlock the Developer mode. Go into Settings->System->Developer options, and enable "USB debugging" and "OEM Unlocking". Turn off the phone. Use the following commands to unlock the bootloader: .. code-block:: bash mtk e metadata,userdata,md_udc mtk da seccfg unlock Make a backup ------------- It is of utmost importance to back up the original software on your phone. This way if anything goes wrong, you can easily go back and start from scratch. You'll need about 5 GB of free space on your hard drive. .. code-block:: bash mkdir f21_stock_rom mtk rl --skip userdata f21_stock_rom Flash the new system -------------------- Turn on your phone and enable "USB debugging" in the settings again. Reboot into fastboot mode: .. code-block:: bash adb reboot fastboot Erase user data if you are upgrading from the stock ROM. Updating Dumbdroid doesn't require this step, unless you are downgrading from GApps to Vanilla. .. code-block:: bash fastboot erase userdata fastboot erase metadata Flash Dumbdroid. Make sure you unpack the zip archive first!!! .. code-block:: bash fastboot flash system dumbdroid_???.img # replace ??? with the actual filename If you get errors that the system partition doesn't exist, make sure that you are in the proper fastboot mode (use the 'adb reboot fastboot' command or enter fastboot mode from recovery). You should see "Fastbootd" written at the top of the screen on the phone. If you get errors that the system partition is too small or can't be resized, try flashing the vanilla dumbdroid and switch to g-apps afterwards through Settings->System->Updates. .. code-block:: bash fastboot reboot Booting the system for the first time might take 5-10 minutes. Recover from backup ------------------- .. code-block:: bash mtk wl f21_stock_rom