Galaxy S2 just got a functional Android 11 rom : r/AndroidMasterRace
How to Update Samsung Galaxy S2 GT I9100 with ICS Neat Custom ROM Firmware
Original Unlocked Samsung I9100 Galaxy S Ii 3g One Sim 1gb Ram 16gb Rom 8mp 4.3'' 1650mah Android2.3.4 Fm Radio Smartphone - Mobile Phones - AliExpress
Best custom ROMs for the Samsung Galaxy S2 - CNET
Best custom ROMs for the Samsung Galaxy S2 - CNET
Update Galaxy S2 to Android 5.1.1 Lollipop CM12.1 ROM [unofficial] | Ninja Romeo