It starts that way, with a mark and sweep collector (think Java CMS or the GC of Go). But some applications like games or Facebook are monsters so the GC was ch

It starts that way, with a mark and sweep collector (think Java CMS or the GC of Go). But some applications like games or Facebook are monsters so the GC was changed to a copy collector which has a better throughput, avoid fragmentation at the cost of using more memory. Also the code is not just AOTed, Android is using profile guided AOT. After several days of usage, the code is AOTed with the profile collected from previous runs.