Day by day the official Android 5.0 Lollipop update is starting to roll out for many flasgship devices with some good specs and features. But if you are amongst those users who haven’t got this latest update officially, then you may prefer flashing those unofficial third party custom ROMs on your phones. The teams of developers have already started to work on creating custom ROMs based on the Google’s new operating system. The most preferred ROM after Cyanogenmod is the recently introduced Omni ROM. This ROM is increasing so rapidly that every other phone has this Omni ROM update. Samsung Galaxy S2 i9100G is an aging device now with no further official firmware after Android 4.1.2 Jelly Bean. This device did get many custom ROMs based on the Android 4.2, 4.3 and 4.4. And it was expected that this phone will get the newly launched Android 5.0 Lollipop update soon. But this time due to the hard work of the Omni ROM developers the i9100G users have received the Android L update much early than expected. So if you want to experience this Android 5.0 Lollipop based Omni ROM on your Galaxy S2 i9100G smartphone then you’ve come at the right place. We’ll discuss a detailed step by step procedure to do the same.

By flashing Omni 5.0 ROM on your Galaxy S2, you can have all the features of Android 5.0 Lollipop on your smartphone. Also Omni ROM comes with some extra features, apps and capabilities which can surely improve your device performance thus making run faster. Along with that your device will be energized with more power, an upgraded battery life, improved web browsing experience and a redesigned Android OS which has been optimized easily. Just follow some simple steps given in this article and by the end of procedure, your Galaxy S2 i900G will be running Android 5.o Lollipop. So let’s begin.

Galaxy S2 i9100G Android 5.0 Lollipop Omni ROM screenshot 1Galaxy S2 i9100G Android 5.0 Lollipop Omni ROM screenshot 2


All the step mentioned below should be performed at your own risk .Don’t even think of trying this if you have no idea of you are doing. Only those users who have gone through this stuff before are allowed to proceed further. In case if you brick your phone by performing the steps given in this guide then neither I nor the developers of this ROM will be hld responsible for that. Although there are least chances that your Galaxy S2 i9100G will get bricked or damaged. Still apply everything carefully and without implementing anything by your own.


This Omni ROM based on the latest Android 5.0 Lollipop OS is compatible only and only on Samsung Galaxy S2 bearing model number GT-I9100G. Do not try this on the international variant Galaxy S2 i9100 or any other device. It may cause permanent damage to the phone. So check out the model number of the device you are using. You can confirm the same from Menu–>Settings–>About phone.

  • Check your device battery life before moving ahead. Make sure you’ve charged it at least upto 65% so as to lower the chances of interruption during the Omni ROM flashing process.
  • Ensure that you have backed up every single data present on your phone.This is highly recommended as everything needs to be wiped in the last step of this process. So take a complete backup of contacts, messages, call logs, memos, whatsapp messages etc. Also keep a copy of these on PC for more safety.
  • You’ll find a folder named EFS present in your phones system directory. This folder contains all your phones specific information such as the IMEI, wireless devices MAC addresses, product code, and much more. So a backup of this folder is essential. There is always a risk that this EFS folder might get corrupted. If so happened, your device will be completely useless & will no longer be recognized by your carrier. Refer our article to backup and restore EFS/IMEI data:
  1. How to backup and restore EFS/IMEI on Android Phones.
  • Make sure you have installed mobile specific drivers on your PC. This is recommended so as to recognize your Galaxy S2 i9100G when connected via USB cable. You can install them by installing Samsung Kies or manually install them from the link given below:
  1. Download latest Samsung USB Drivers.
  • Also ensure that your Galaxy S2 i9100G is rooted.
  • A custom recovery like Clockworkmod (CWM) or TWRP must be installed before proceeding further.

So are you ready with everything. OK then let’s move to the actual Android 5.0 Lollipop ROM flashing process now.

Procedure to install Android 5.0 Lollipop on Galaxy S2 i9100G:


  1. Download Omni 5.0 Custom ROM for Samsung Galaxy S2 i9100G.
  1. Download Google Apps (Android 5.0 Lollipop).


Step 1: After downloading both the ROM package file and the GApps file on your PC, connect your Galaxy S2 i9100G to PC using the USB cable.

Step 2: Copy both these package files on your phones SD card. Then safely disconnect the device from PC & switch it off completely.

Step 3: You need to enter into custom recovery mode now. For that press & hold ‘Volume up + Home button (middle button) + Power button simultaneously until recovery mode appears.

Note: Touch won’t work in recovery mode. So use Volume up and down keys for navigation and Home button for selection.

Firstly make a complete nandroid backup which is nothing but the backup of your phones entire operating system & is always helpful during the failure while flashing process or during any problem with the ROM, then you can easily restore your saved previous ROM.

Refer our detailed article for taking Nandroid backup:

  1. How to take Nandroid Backup of any Android Phone with 8 simple methods.

Step 4: A complete nandroid backup can be take by first navigating to the ‘backup & restore’ option on the recovery mode. On the next screen select ‘backup’ option. This will make a complete nandroid backup of your current using ROM.

Nandroid backup screenshot 1Nandroid backup screenshot 2

Step 5: Then return back and using Volume keys navigate to the ‘wipe data/factory reset’ option and select it using Home button. On the next screen select ‘wipe cache partition’ option. This will clear all the data & caches from your phones internal memory. Make sure you have backed up everything before performing this step (refer prerequisites section).

CWM wipe data cache screenshot

Step 6: Next navigate to the Advanced option located on the recovery mode. Select it using home button and on the next screen select Reboot Recovery  option. This will reboot your phone and will land again into recovery.

reboot recovery screenshot

Wait until you boot again into recovery.

Let’s move to the actual Android 5.0 Lollipop based Omni ROM installation process on your Galaxy S2 i9100G.

Step 7: To flash the ROM navigate to the ‘install zip from SD card’ option located on the recovery. Select it using Home button. Then on the next screen select ‘choose zip from SD card’ option. This option will show you all the data present on your phones external SD card. Select the Omni Custom ROM which you’ve copied earlier. On the next page select ‘Yes’ option to initiate the flashing process. Be patient till the process completes successfully.

CWM recovery Screenshot

Step 8: After completing the flashing process, you’ll again land into recovery mode. Then again select ‘wipe data/factory reset’ option followed by ‘wipe cache partition’ option on the recovery mode to clear all phones data & cache. This step is essential to solve the boot loop issue.

Step 9: Similarly flash the Google Apps as you’ve flashed the Omni ROM. Just remember not to wipe data/cache after flashing them.

Step 10: You may restart your Galaxy S2 i9100G by selecting ‘reboot system now’ option from the recovery mode. This first boot takes more time to start than usual.

reboot system screenshot

Note: If you want to restore back your previous Rom, then you can do that by going back to the recovery mode by pressing & holding Home Button (middle button) +  Power Button simultaneously and select ‘Backup and Restore’ option and then on next page select ‘Restore’ option. Select the ROM you want to restore.


Haha! Your Samsung Galaxy S2 i9100G has been successfully updated to Android 5.0 Lollipop based Omni Custom ROM. Go to Settings->About Phone to confirm the same. This is the full featured ROM developed for Galaxy S2. So enjoy it and share your views & experience after using it. If you face any problem while going through the process just inform me. I’ll be glad to help you out. 🙂

Also Read: How to Fix Google Play Store Errors in any Android phone.

Also Read: How to Increase Internal Memory of any Android Smart Phone.

Also Read: How to Crack Unlock Pattern/Password/Pin lock of any Android Smart Phone.