<--Google Page ads-->

Flash Unofficial CM 10.2 Test Build for Samsung Galaxy S2 I9100G (Android 4.3 Jelly Bean custom ROM)

Android 4.3 Jelly Bean has been officially pushed out for Nexus devices not long ago and now developers begun work on releasing test builds that will work on other Android devices too. This tutorial will teach you how to successfully install an Unofficial CyanogenMod 10.2 test build Custom ROM for the Galaxy S2 I9100G, the TI OMAP model.

In order to make sure that you successfully update your smartphone with this guide, you will first need to take a look at the preparation guide below. You will learn exactly how to correctly configure and prepare your device for the updating process. Here’s what you need to know:

  • Use this post only with the International Samsung Galaxy S2 with the model number I9100G. This is the Ti OMAP CPU variant and not the Exynos one.
  • Do not attempt to flash the files you find here on any other Android smartphones.
  • Your device has to be factory unlocked, rooted and running a custom Recovery mode such as TWRP or CWM.
  • In this post you’ll find instructions for both TWRP and CWM Recovery modes.
  • Before starting the installation you should create a full NANDROID backup of your current OS. This will act as a restore point that can be used in case you have problems with the updating process.
  • In the ‘how-to’ part you will find a step that asks you to wipe data and factory reset the phone. This means that all installed apps, SMS, call logs info and other similar system partition files will be deleted.
  • If you want to backup data from installed apps and then restore them after the Unofficial CM 10.2 ROM is installed, then you should use Titanium Backup tool for rooted devices.
    > NOTE: this new ROM might not work with the TITANIUM BACKUP app, which is why you should only use the app if you know what you’re doing.
  • In order to backup SMS, Call Logs info and APN Internet Settings, then you should use the following apps: SMS backup & restore | Call Logs backup & restore | APN Settings Backup & Restore. Root access is needed for this tutorial.
  • Sync the Contacts info with your Gmail account. This will help you backup all the saved phone numbers and Contacts data.
  • Enable USB debugging from Developer Options.
  • Make sure that your Galaxy S2 I9100G has enough power left in its battery before starting the update. In case your device powers off in the middle of the updating process, then you will need to repeat the entire once again.
  • Read all the info listed in this post and make sure that you don’t skip any steps.
  • Note that this is a tutorial destined for advanced users who want to test this unofficial CM 10.2 ROM and the latest Android 4.3 Jelly Bean AOSP firmware on their devices.
  • We cannot be blamed if your device gets bricked in the process nor in case you lose any important data files in the process.
  • If you’re having problems with the installation process, then you should ask for more help in comments.

Now that you know all of the above, continue to the next part of this post and learn how to update your device with a test build based on the latest Jelly Bean 4.3 firmware. More info about this release can be found at its XDA thread here.

How to install Unofficial test build of CM 10.2 based on Android 4.3 Jelly Bean for Samsung Galaxy S2 I9100G:

  1.  Download the CM 10.2 Unofficial ROM zip from here.
    > save the file on your computer.
    > do not unzip its contents.
  2. OPTIONAL: Download Gapps for Jelly Bean zip from here.
    > this is an optional download as you don’t need to flash this file, but you might still need it in case the new ROM doesn’t feature any Google Apps.
    > if the Unofficial CM 10.2 doesn’t have the Google apps, then you need to return to this tutorial and install Gapps too. The ROM zip doesn’t have to be re-installed.
  3. Connect your Galaxy S2 I9100G to your PC and then move the zip files to your phone’s internal SDcard.
  4. When the files are copied, disconnect the phone from computer.
  5. Power off your Galaxy S2 now.
  6. Boot it into Custom Recovery Mode.
  7. The first thing that you need to do is to create a NANDROID backup of your current ROM.
    > for CWM Recovery users: select ‘backup and restore’. Confirm.
    > for TWRP Recovery: press Backup, select the system parts you wish to backup, then confirm the process.
  8. Next apply a factory reset for your device.
    > NOTE: if your phone is running on a previous CM 10.1 build, then you can skip this step.
    > CWM Recovery: select ‘wipe data/ factory reset’. Confirm.
    > TWRP Recovery: press Wipe, then Factory Reset button and confirm.
  9. Now you can flash the Unofficial CM 10.2 ROM test build for your Galaxy S2 I9100G:
    > CWM: select ‘install zip from sdcard’, then ‘choose zip from sdcard’. Find the Unofficial CM 10.2 zip and confirm the installation.
    > TWRP: press Install button, then you need to browse your phone’s internal SDcard for the CM 10.2 zip file. Confirm that you wish to install it by sliding to the right the blue button.
    > the installation shouldn’t take long to complete.
  10. Flash the Gapps zip file just like you did with the ROM.
  11. Return to the main Custom Recovery menu after the isntallations have been completed successfully.
  12. Reboot your smartphone into normal mode.
    > note that the first boot process might take a while before loading all the required files.
  13. Enter your Google Account details when the home screen appears.
  14. Take control over your device and then start testing all the new CM 10.2 test build features and functions.

I hope that you’ve managed to successfully update your Galaxy S2 I9100G with this new custom ROM. In case the new files weren’t installed or you hit any roadblocks, then you should repeat the entire tutorial once again, as usually custom ROMs might not flash successfully at the first attempt. Use the comments field to ask for extra help.

In case you don’t like how the Unofficial CM 10.2 ROM works with your Galaxy S2 I9100G, then you should use the NANDROID backup file created in step 7 and restore your device to its previous state.