Install Android 5.1.1 Lollipop CyanogenMod 12.1 on Galaxy S2 I9100

The Custom development is one of the Biggest reason why Android is still on the top and why the old Flagship devices are still active in the market, I mean Galaxy S2 arrived in market almost 4 years ago, February 2011 and received the best Smart-phone of all times award and even the Galaxy S3 wasn’t able to reach such heights that S2 was standing on, although, it became old and now there is no official support for this device anymore, the last official update for this device was the Android 4.1.2 Jelly Bean and afterwards, the Custom Development has kept this device alive and most probably it will remain alive in coming years too.

CyanogenMod 12.1 which is based on Android 5.1.1 Lollipop has arrived for Galaxy S2 I9100, CyanogenMod is based on Pure Android and AOSP sources, so if you are running any Stock based ROM on your device, then say goodbye to all the Gimmicks and move on to something simple and fast. You’ll get all the features of Android 5.1 Lollipop and most probably, alot of speed and better battery timing is waiting for you.In this article, we will show you How to Install Android 5.1.1 Lollipop CyanogenMod 12.1 on Galaxy S2 I9100, however, if you are interested in Other ROMs, you can Visit our Custom ROMs section or you can install this ROM on your Galaxy S2 I9100 by following our tutorial below. This is not an official release from Samsung but a Custom ROM. Installation procedure uses the Fastboot commands to install this custom ROM. Your device must be rooted. Let’s go through the early preparations and then flash this ROM.

Install Android 5.1.1 Lollipop CyanogenMod 12.1 on Galaxy S2 I9100

Early Preparations:

  • This is only for Galaxy S2 I9100!
  • Battery should be charged at least over 60%
  • Unlock Bootloader Of Your Device.
  • Flash a Custom Recovery and Root Your device
  • Backup SMS Messages
  • Backup Call Logs
  • Backup Contacts
  • Backup Media – Copy your files manually to your PC or Laptop.
  • Titanium Backup – If already rooted, use Titanium Backup to backup all of your apps, system data and other important content.
  • Backup Nandroid –  If CWM  or TWRP installed previously, otherwise skip this step and perform this at the end of flashing


The methods involved in flashing custom recoveries, roms and rooting your phone are highly custom and may result in bricking your device, and has nothing to do with Google or the device manufacturer that is Samsung in our case. Also rooting your device will void its warranty and you will be no longer eligible for any kind of free device services by the manufacturers/warranty providers. In case of any mishap we may not be held responsible. Follow these instructions to the letter to avoid any mishap or bricking. Make sure that whatever you do, you are doing it at your own responsibility.

Downloads Required:

CyanogenMod 12.1: Link

Gapps: Link | Mirror

How to Install CyanogenMod 12.1:

  • Connect your device with PC.
  • Copy and Paste the Above zip files to the root of your sdcard.
  • Open Recovery mode. How?
  1. Connect your device with PC
  2. Open Command Prompt in Fastboot folder. (ADB and Fastboot Tools Installer)
  3. Now Type: adb reboot bootloader
  4. Choose Recovery from Bootloader

CWM/PhilZ Touch Recovery:

  1. Back-up your ROM using the Recovery.
  2. To Perform a Back-up, Navigate to Back-up and Restore on Next screen, Choose Back-up again.
  3. Go back to Main Screen after the Back-up is complete.
  4. Then Navigate to ‘advance’ and choose ‘Dalvik Wipe Cache’, so you won’t get in any bootloop.
  5. Navigate to ‘Install zip from sd card’ another windows will open in front of you.
  6. Finally Select “Wipe Data/Factory Reset”
  7. Select ‘choose zip from sd card’ from the Options.
  8. Select the CyanogenMod file and confirm the installation on next screen.
  9. Go Back and Flash
  10. Once the Installation is Over, Select +++++Go Back+++++
  11. Select Reboot Now to Reboot the System.

TWRP Users.

  1. Tap On Back-Up and Select System and Data
  2. Swipe the Confirmation Slider
  3. Tap on Wipe Button and Select Cache, System, Data.
  4. Swipe the Confirmation Slider.
  5. Go back to Main Menu and Tap Install Button.
  6. Locate the CyanogenMod, and Swipe the Slider To install it.
  7. Once the Installation is Over, you will be promoted to Reboot System Now
  8. Select Reboot Now to Reboot the System.

The First boot might take up-to 5 minutes, so please be patient.

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