# Download Android source with local_manifests Refer to http://source.android.com/source/downloading.html $ repo init -u https://android.googlesource.com/platform/manifest -b android-12.1.0_r21 $ git clone https://github.com/android-rpi/local_manifests .repo/local_manifests -b arpi-12 $ repo sync # Build for Raspberry Pi 4 https://github.com/android-rpi/device_arpi_rpi4/tree/arpi-12 Use -j[n] option on sync & build steps, if build host has a good number of CPU cores.