Everyday is a new day for new custom ROMs to be tried and tested. If you constantly take a trip to the XDA Forums, you'll probably find two or three custom ROMs that are promising enough for you to actually install on your device. Today, we will be showcasing one promising custom ROM for the Samsung Galaxy S Plus GT-I9001.

Among a plethora of custom ROMs, the SmoothieJB ROM developed by XDA Developers member Brahmnoor is faster, smoother, and slimmer. SmoothieJB features CM10 by Ivendor Alpha 5 and BroodKernel v1.4 and does not have annoying bloatware. The developer has incorporated system tweaks for better hardware support, better GPS and maps, and gaming tweaks. This ROM's only bugs are some minor glitches when taking panorama shots and the requirement of Vsync for the full Project Butter experience.

This guide shows you how to upgrade the Galaxy S Plus I9001 to Jelly Bean via SmoothieJB ROM.

Warning

• The instructions in this guide are intended for use with the Samsung Galaxy S Plus, model number GT-I9001. Applying these instructions on another device or model may produce undesired outcomes.
• The information in this guide is provided for instructional and educational purposes only. There is no guarantee that these instructions will work under your specific and unique circumstances.
• Use these instructions at your own risk. We shall not hold any responsibility or liability for whatever happens to you or your device arising from your use of the info in this guide.
• Read and understand the whole guide first before actually performing the instructions.

Requirements

• A Samsung Galaxy S Plus GT-I9100 with ClockworkMod Recovery installed.
  • For help, check our guide on how to install ClockworkMod Recovery on the Galaxy S Plus I9001.
• Download the following files to your computer:
  • SmoothieJB v2 ROM package (SmoothieJB-v2.zip, md5sum: 038b47cbb8bb9de3dd2a2a308f1868fe)
    • Original Link
    • Mirror
  • GApps (Google Apps) package (gapps-jb-20121011-signed.zip, md5sum: 4e9e7ec3c22b0b3471bd05d62b8a659d)
• See to it that your phone's battery is charged up to 75% or more to avoid interruptions during the process.
• Backup all personal data on your phone to make sure you have a copy of your personal data (e.g., contacts, SMS, MMS, Internet settings, Wi-Fi passwords, and the like) in case the procedure in this guide erases such data.
  • For backup tips, check our guides on how to sync your data to the cloud and how to create local backups of your mobile data.

Instructions

1. Copy the SmoothieJB ROM package and the GApps package to your phone's SD card.
2. Switch your phone off.
3. Boot into ClockworkMod Recovery. To do this, press and hold down the Volume Up and Power keys together. 

   As soon as an Android box icon shows up, press the Menu Button to enter recovery.

   • NOTE: You can use the Volume keys to navigate and the Power button to select an item or option in recovery.
4. Make a NANDroid backup of your current ROM. To create a backup, go to Backup and Restore and select Backup.
5. Select Wipe Cache Partition and confirm the action on the next screen.
6. Go to the main menu and select Advanced. From there, select Wipe Dalvik Cache and confirm the action on the next screen.
7. Select Wipe Data/Factory Reset and confirm the action on the next screen.
8. Select Install ZIP from SD Card.
9. Select Choose ZIP from SD Card and navigate to the SmoothieJB ROM file. Select the file and confirm the action on the next screen to start installing the ROM to your phone.
10. After installing the ROM package, repeat steps 8 and 9 to install the GApps package.
11. Once the GApps package is installed, go to Advanced and select Fix Permissions. Wait for the process to finish.
12. Select Go Back and select Reboot System Now. This will reboot your phone to the newly installed SmoothieJB ROM.

High five! You have successfully upgraded your Samsung Galaxy S Plus GT-I9001 to Jelly Bean via the SmoothieJB ROM. If you have comments about this ROM, post them below.