Depending on your device, the installation method varies significantly: Official Flash Tool (Pixel Devices) : Google provides a web-based Android Flash Tool
: This method allows you to load an Android 12 Generic System Image (GSI) alongside your current system as a "guest OS" without needing a computer, provided your device supports dynamic partitions. OpenAndroidInstaller Android Installer V12
Under the hood, Android 12 claimed to reduce the CPU time needed for core system services by 22% and the use of big cores by 15%. For users with older hardware, installing this version (or a lightweight custom ROM based on it) was a way to breathe new life into aging phones. Depending on your device, the installation method varies