Looking for a great and properly working Ice Cream Sandwich Android 4.0 ROM for your Galaxy S Plus I9001, the device Samsung decided not to given even one official Android version update? Well, it seems you search may be at an end.

XDA Senior Member ivendor has released CM9 ROM for the I9001, based on Ice Cream Sandwich and featuring the fast performance and useful customization options of CyanogenMod, without the bloat and unnecessary apps found in stock Samsung ROMs. The best part is that the ROM works pretty good and has almost everything working so it’s a great way to try out Ice Cream Sandwich on your I9001.

Currently, the following things do not work in the ROM (quoted from the developer):

Not working:
FM radio (will probably never work due to lack of sources)

NOTE, Please Read: Since this is an AOSP based ROM, some features like 3G video calling will be unavailable as those are only possible on stock Samsung ROMs (video calls using 3rd party apps like Skype will work fine though). Some other features such as an FM radio will be missing too, and some apps like camera may not be the same as on stock ROMs.

Let’s take a look at how CM9 can be installed on the Galaxy S Plus.

Compatibility

This recovery and the guide below are compatible only and only with the Samsung Galaxy S PLUS, model number i9001. It’s not compatible the GT-i9003, I9000 or with any other device and may render an incompatible device unusable. Check your device model in Settings » About phone.

Warning!

The methods and procedures discussed here are considered risky and you should not attempt anything if you don’t know exactly what you are doing. If any damage occurs to your device, we won’t be held liable.

How to Install CM9 on Galaxy S Plus I9001

1. This procedure will wipe all your apps, data and settings (but it will NOT touch your SD cards, so don’t worry about those). Backup your Apps and important data — bookmarks, contacts, SMS, APNs (internet settings), etc. This Android backup guide would help you.
   NOTE: Don’t forget to at least make a backup of your APN settings, which you can restore later if your data connection does not work after installing the ROM. Use the backup guide to find out how.
2. Remove SIM card lock, if you have set it earlier. Go here: Settings » Location and Security » Sim card lock » checkbox should be clear (not selected).
3. Install TWRP Recovery on your phone by following the guide → here.
4. Download the latest version of the ROM from its development page.
5. Download the Google Apps package. This will install apps like Play Store, Gmail, etc. which are not present in the ROM by default.
   Download Gapps  |  Alternate Link  |  Filename: gapps-jb-20120726-signed.zip
6. Copy the two zip files downloaded in step 4 and 5 to the internal SD card on the phone.
7. Now, we need to boot the phone into TWRP recovery. To do so, turn off your phone. Then, press and hold the Volume Up + Power buttons together, and let go of the buttons as soon as the Samsung logo shows up. Then, as soon as an icon showing “an Android in a box” comes up, press the Menu button (the button on the left of the center/home button) to enter recovery.
8. Now, tap on Backup, then slide the blue circle button at the bottom to the right to start backing up your current ROM, so that you can restore it later if something does not work out with the new ROM. After backup is complete, go back to the main menu by clicking the home button at the bottom left of the screen.
9. Select Wipe, then select Factory Reset and then confirm the data wipe. This will not wipe your internal SD card’s contents, so do not worry. Then, go back to the main menu by clicking the home button after wipe is complete.
10. Select Install, then browse and select the ROM file on the SD card. Confirm installation to flash it.
11. After installation of ROM is complete, repeat step 10, but this time select the gapps-jb-20120726-signed.zip file you downloaded in step 5 above. Confirm again to install the Gapps package.
12. After installation is complete, select the Reboot system button to reboot the phone and boot up into CM9. First boot will take up to 5-7 minutes.
    NOTE: Returning to Previous ROM. In case you want to go back to your previous ROM, boot into recovery (with procedure explained in step 7), select Restore, then restore your previous ROM by selecting it from the list. Then reboot the phone after restore is complete.

CM9 based on Android 4.0 is now installed and running on your Galaxy S Plus. Visit the development page for more info and to get the latest updates on the ROM. Share your thoughts on the ROM in the comments.

Android 4.0, CM9, custom ROM, CyanogenMod 9, Galaxy S Plus, GT-I9001, guide, I9001, I9001 CM9, Ice Cream Sandwich, ICS, Samsung