How to galaxy s2 update (i9100) to lollipop with CM 12.1

The Samsung galaxy S2 was released on 13th of February 2011. Actually for now also this is a good phone that everyone loves. The model I'm going to show you is I9100, it is the international version of galaxy s2. This phone is with Dual-core 1.2 GHz Cortex-A9 processor and with 1GB ram. This phone got official updates till jelly bean. After that they stop sending updates for this phone. But we can update this phone to the latest version of android with CyanogeMod. Here you will get the full tutorial of galaxy s2 update to lollipop.

Pre- Requisites

  • You can update to Lollipop from any android vesrsion
  • This tutorial is for Samsung Galaxy S2 I9100 version. Verify it by navigating to settings>About.
  • The battery status should be above 80%.
  • Use correct usb drivers for the PC.
  • Enable usb debugging in phone.

Downloads

Steps to Galaxy S2 Update to Lollipop with cyanogen mod 12.1

  • Read Following steps carefully for Galaxy S2 Update
  • 1.Copy these 4 files to phone’s internal storage by connecting with USB.
  •   "cm-12.1-20150617-UNOFFICIAL-i9100.zip"
  •   "ROOT-UPDATE-SuperSU-v2.46.zip"
  •   "gapps-5.1.x-20150404-minimal-edition-signed.zip"
  •   "Alternative Apps" (unzip this)
  • 2.Switch off the phone and switch on it by pressing volume down + home button + power button together
  • 3.After you correctly entering to the Download mode connect your phone to the computer with USB.
  • 4. Then open “Odin” in your computer. And on the top the box near to the ID:COM should be blue color that means your phone correctly detected by Odin
  • 5.Then untick "Auto Reboot" and select "CM-12-Kernel+Recovery-I9100.tar" file to PDA (see the image below)
  • 6.Then click "START"
  • 7. After finishing this you can see "RESET!" on a blue color box then wait about 1 minute and remove the phone.
  • 8. Then switch off the phone by removing the battery.
  • 9.Then enter to the recovery mod by pressing Volume up + home button + power button together
  • 10. Then
  •   Wipe Data/Factory reset
  •   Wipe Cache partition
  •   Wipe Dalvik cache (advanced > Wipe Dalvik cache)
  • 11. Then install the files
  • Navigate to "Install zip > Choose zip from /storage /sdcard" and select "cm-12.1-20150617-UNOFFICIAL-i9100.zip" and install, and do the same for "ROOT-UPDATE-SuperSU-v2.46.zip" and "gapps-5.1.x-20150404-minimal-edition-signed.zip".
  • 12. After finishing all these reboot the phone. Remember the first boot can take a little longer than usual.
  • 13. All done now you have a successfully updated Galaxy s2.

Video Tutorial