: The rINanDO galaxys2-patches repository contains the build instructions for developers.
Because modern Android apps require significantly more RAM than the S2 possesses, the phone will feel very slow. Battery life is also a major concern, as modern OS background processes are not optimized for 15-year-old battery tech. How to Install (The General Process)
While the Samsung Galaxy S2 (GT-I9100) officially stopped receiving updates at Android 4.1.2 Jelly Bean , developers have successfully ported Android 13 to this 15-year-old device using custom ROMs. The Android 13 Experience on Galaxy S2