There are numerous benefits to installing CM11 ROM on your handset; one of the biggest is that it comes without bloatware.
Anyone who owns the handset and who wants to install it on their device should check below.
Requirements:
1. Flash this firmware to the Samsung Galaxy S2 GT-I9100 only.
2. Root the smartphone then install a custom recovery such ClockworkMod recovery.
3. Install the necessary USB drivers for your Galaxy S2 on your computer.
4. Create a manual backup of all personal information, settings and data files stored on your handset.
5. Make sure that the battery level is at least 50 per cent to prevent any power interruption during the flash.
6. Enable USB debugging mode on your device. Go to “Settings > Applications > Development > USB debugging mode” or “Settings > Developer options > USB debugging.”
7. Download the CyanogenMod 11 for Galaxy Note N7000 and the Google Apps package to your computer.
Flashing Instructions:
1. Connect your Samsung Galaxy S2 GT-I9100 to your computer using a USB cable.
2. Copy the CyanogenMod 11 and the Google Apps package to the SD card of Galaxy S2. No need extract the zip files.
3. Disconnect the phone from the computer then turn it off.
4. Reboot into Recovery mode by pressing and holding the Volume Up, Home and Power keys at the same time till the Samsung logo appears.
5. Inside the Recovery mode, create an Android backup of the current ROM. Select “backup and restores > backup.” You may restore the saved ROM inside the SD card anytime.
6. Perform a full wipe on your device. Select “wipe data/factory reset” and “wipe cache partition.” Then select “advanced > wipe Dalvik cache.”
7. Go back to the main menu then install the CyanogenMod 11 by selecting “install zip from SD card > choose zip from SD > search the ROM you have copied earlier > confirm installation.” Apply the same with the Google Apps.
8. Once the installation has been completed, go back then select “reboot system now.”
9. It may take at least five minutes before the Galaxy S2 reaches the home screen after rebooting.
If things have gone well when you reboot you should have KitKat 4.4 on your Samsung Galaxy S2.
