Install Android 5.1.1 Lollipop CM12 on Galaxy S Plus i9001. This device was launched with Android 2.3 Gingerbread OS but unfortunately it didn’t get any further updates from Samsung. This smartphone is considered to be the most lucky one as it received maximum number of unofficial custom ROMs from third party developers. Due to which the Galaxy S Plus users were able to experience the newly launched Android versions on their phone. Recently, the recognized XDA developer Christopher83 has developed Cyanogenmod 12.1 ROM based on the latest Android 5.1.1 Lollipop OS especially for Samsung Galaxy S Plus GT-I9001 smartphone.

Install Android 5.1.1 Lollipop CM12 on Galaxy S Plus I9001 screenshot 1

As Galaxy S Plus has 1.4 GHz Qualcomm Scorpion processor with 512 MB of RAM, we can say that this CM12.1 ROM may run smoothly on it. The developer says that the ROM is highly functional with almost every feature and function working. this ROM is so beautifully customized that you’ll enjoy and experience the combined features from Android 5.1.1 Lollipop OS and Cyanogenmod 12.1 on your Galaxy S Plus. Interested users who want to experience the Android 5.1.1 Lollipop CM12.1 ROM on Galaxy S Plus I9001 may proceed to our actual article given below.

Install Android 5.1.1 Lollipop CM12 on Galaxy S Plus I9001 screenshot 2

Working List:

  • Audio
  • MTP storage
  • Proximity sensor
  • F2FS support for /data partition
  • Acceleration
  • Gravity sensor
  • Voice video calls
  • USB/Wifi tethering
  • Rotation vector
  • Wifi
  • MicroSD
  • exFAT support
  • Bluetooth
  • Camera
  • Receiving and making calls
  • GPS
  • Light sensor
  • Orientation
  • Compass
  • Linear acceleration
  • Phantom key presses filtering

Install Android 5.1.1 Lollipop CM12 on Galaxy S Plus I9001 screenshot 3

Each and every step mentioned below must be tried at your own risk. Neither I nor the developers of this ROM will be held liable if any damage occurs to your Galaxy S Plus by following this guide. Although I assure you no such thing will happen if implement every step correctly without a single mistake. This guide is only for Samsung Galaxy S Plus bearing model number GT-I9001. Do not use this for any other device or variant. If tried your  device may turn into semi bricked / non functioning state.

Install Android 5.1.1 Lollipop CM12 on Galaxy S Plus I9001 screenshot 4


  • Charge your Galaxy S Plus at least up to 60% as lack battery can interrupt the process.
  • Backup all your data including contacts, messages, call logs, apn settings, memos etc. You may use Super Backup app for the same.
  • A folder called EFS present in your phones system directory contains all your phones specific information such as the IMEI, wireless devices MAC addresses, product code, and much more. If by mistake this folder gets wiped out then 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.
  • Your Samsung Galaxy S Plus must be Rooted.
  • Make sure you have installed mobile specific drivers on your PC. This is important so to recognize your phone 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.
  • Make sure you have installed latest custom recovery like Clockworkmod (CWM) or TWRP before flashing this CM 12.1 ROM. If not, then don’t worry just follow the steps given below:

Step 1: Download and copy this TWRP recovery on your phones external SD card.

Step 2: Switch off your Galaxy S Plus completely and boot it into recovery mode.

Step 3: For the same, press and hold Volume up + Home button (middle button) + Power button simultaneously until you land into stock recovery mode.

Step 4: Using Volume keys navigate to the ‘apply update from SD card’ option and then select this TWRP recovery using Home button. This will start the TWRP recovery flashing process.

Step 5: After successfully flashing it, return to the main menu and select reboot system now option to restart your Galaxy S Plus.

That’s all! You’ve flashed the latest TWRP recovery. Let’s flash the Android 5.1.1 Lollipop ROM CM12.1 now.

Procedure to install Android 5.1.1 Lollipop on Galaxy S Plus:


  1. Download Android 5.1.1 Lollipop CM12 ROM for Galaxy S Plus I9001.
  1. Download  Google Apps for Galaxy S Plus I9001.


Step 1: Download both the zip package files on your PC. Do not extract them.

Step 2: Then connect your Galaxy S Plus to PC using USB data cable, enable mass storage mode and transfer both the downloaded files on your phones SD card.

Note: If your PC doesn’t recognize your Galaxy S Plus, make sure device specific drivers are properly installed or you may change USB cable or port.

Step 3: Disconnect your phone from PC & switch it off completely until it vibrates. Now enter your phone into TWRP recovery mode. The same can be done by pressing & holding Volume up + Home button (middle button) + Power button together till you land into TWRP recovery.

At first make sure you take nandroid backup of your current ROM. This nandroid backup is the backup of your 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: For taking nandroid backup, click on the Backup option present on the main menu of recovery. Swipe on the next screen to start the backup process.

Install Android 5.1.1 Lollipop CM12 on Galaxy S Plus I9001 nandroid backup screenshot

Step 5: Then you need to wipe the data/cache present on your device. So press back button to return to main menu of recovery and select the Wipe option. On the next screen swipe to wipe all the data/cache from your phone.

Install Android 5.1.1 Lollipop CM12 on Galaxy S Plus I9001 wipe data screenshot

Note: This step will clear all the data & caches from your phones memory. Hence a backup of entire data must be done before implementing this step.

Let’s flash the Android 5.1.1 Lollipop based CM 12.1 ROM now.

Step 6: After wiping out everything press back button and select the Install option. This will show you all the files present on your phones memory.

Step 7: Just navigate to the Android 5.1.1 Lollipop based Cyanogenmod 12.1 custom ROM and select it. On the next screen just swipe to start the actual flashing process.It will take few minutes to complete successfully.

Install Android 5.1.1 Lollipop CM12 on Galaxy S Plus I9001 install CM12.1 screenshot

After completion, you’ll see the successful message on the screen.

Step 8: Similarly flash the Google Apps (containing Google Play Store, Maps, Gmail, GTalk etc.) as you’ve flashed this Cyanogenmod 12.1 custom ROM. Don’t wipe data/cache after flashing it.

Step 10: After completing everything mentioned above, restart the phone by selecting the Reboot option present on the recovery mode itself. Note that it will take more time to start than usual.

Install Android 5.1.1 Lollipop CM12 on Galaxy S Plus I9001 reboot screenshot

Note: If you want to restore back your previous Rom, then you can do that by going back to the TWRP recovery and selecting Restore option. Then select the saved you want to restore.


Hurray! You have successfully flashed the latest Cyanogenmod 12.1 custom ROM based on Android 5.1.1 Lollipop OS on your Samsung Galaxy S Plus GT-I9001 smartphone. You can confirm the same from Menu->Settings->About Phone. Enjoy the combined features of Android Lollipop and Cyanogenmod 12.1 on your smartphone. Don’t forget to share your experience after using it. If you have any problem, query or suggestion regarding the guide then you may ask me through the comments. I’ll be glad to help you. Till then Enjoy! 🙂

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.