Samsung Galaxy S2 I9100G can be updated to Android 4.2 Jelly Bean with CyanogenMod 10.1 (CM10.1) which offers a lot of custmomization to the users. CyanogenMod 10.1 is in early stage and there may be bugs and few features of Stock ROM may not work.
The guide mentioned below is only for Samsung Galaxy S2 i9000G and cannot be tried on any other device. You can check Model number of device by going to Settings >> About phone.
We cannot be held liable of any damage done to your device while following the below mentioned procedure.
Install CM10.1 Android 4.2 on Samsung Galaxy S2 i9000G
Take a complete backup of data,apps and settings as the procedure may wipe your data.
Make sure that the battery of device has a minimum charge of 60%.
Enable “USB debugging” on your device by going to Settings >> Developer options >> Enable USB debugging.
Clockworkmod recovery should be installed on your device.
Android 4.0.3 XXLPQ firmware should be installed.
Download ROM from here and Google apps package from here.
Copy both the zip files to your device SD-Card without extracting.
Switch off device and boot into recovery mode. You can do that by holding and pressing Volume up, Home and Power buttons together and then select recovery by using Volume buttons.
Take a Nandrop backup of your existing ROM so that you can revert if things don’t work out fine.Select “Backup and Restore” and then select “Backup” again. Now, go back to main recovery menu once backup is complete.
Select “wipe data/factory reset” and confirm to wipe data. Wait for few minutes till the data is wiped.
Select “install zip from sdcard” and select “choose zip from sdcard”. Navigate to ROM file and select to confirm installation.
Again, select “choose zip from sdcard” and select to install “Google apps package”.
Select “Go Back” and select “Reboot System Now” to reboot your device.
CyanogenMod 10.1 based on Android 4.2 Jelly Bean is installed on your Samsung Galaxy S2 I9100G.