Just because the HTC One X is one of the fastest and high-end phones in the Android world, it doesn’t mean its ROMs have to be big in size. Meet Slim ICS ROM, a custom ROM for the One X that clocks in at a very small size of 80MB, and brings the stock Android experience without the Sense UI on top or other bloatware.

The key features of the ROM include:

  • Fully built from AOSP sources with some cherry picks from CM and AOKP team,
  • Easy to customize features (thanks to AOKP team) via ASS (Advanced Slim Settings)
  • 5 languages
  • Lightning Launcher
  • Lockscreen Options ( Calendar, Weather etc, check via ASS)
  • Screenshot via Customizable Nav Bar

The ROM is as slim as it can get, without compromising too much on the functionality. Keep reading to find out how it can be installed on your HTC One X.

Compatibility

This guide is applicable only for HTC One X. DO NOT try this on any other device.

Warning!

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

How to Install Slim ROM on HTC One X

  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.
    Important! 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. Unlock the bootloader on your HTC One X by following the guide → here.
  3. Install ClockWorkMod (CWM) recovery by following the guide → here.
  4. Download and install HTC Sync software on your computer in order to install the required drivers for the phone.
    Download HTC Sync
    Skip this step if you already installed the drivers while following step 2, or if you have HTC Sync installed already.
  5. Download the latest version of the ROM from the official download page. You need to download three files as given below:
    1. Base_HTC_*.*.zip  (where * is the latest version number)
    2. *.*EndeavorU_Essentials.zip  (where * is the latest version number)
    3. Slim_Gapps.zip
  6. Copy the 3 downloaded zip files (don’t extract them) to the SD card.
  7. Also download the Flash_Boot.zip file from → here. This is required to flash the necessary kernel on the phone.
  8. Extract the Flash_Boot.zip file to a convenient location on the computer.
  9. Open the “*.*EndeavorU_Essentials.zip” file on the computer and extract the boot.img file from inside it. Then, copy the boot.img file to the folder where you extracted the Flash_Boot.img file in step 8. You will then have the following files in the folder as shown in screenshot below:
  10. Switch off the phone. Boot into the bootloader mode first by holding the Volume Down button while powering on the phone. Then, select FASTBOOT from there using the volume buttons to navigate and power button to select to enter fastboot mode. Then connect your phone to the computer.
  11. Go to the folder where you extracted the .zip file in step 8. Double-click the flash-boot-windows.bat file to flash the required kernel.
  12. After the kernel is flashed, the window that showed up will automatically close. It might also say OKAY/finished and stay open, which is normal.
  13. Now, press the power button on the phone to select BOOTLOADER, then navigate to the RECOVERY option and select it using the power button to boot into ClockworkMod recovery.
  14. Perform a wipe:
    1. Select wipe data/factory reset, then select Yes on the next screen to confirm data wipe. This will only delete your installed apps and settings, but will leave all other files and data on the SD card intact, so don’t worry.
    2. Select mounts and storage, then select format system (you might have to select Yes on next screen to confirm). After format is complete, go back to the main recovery menu.
  15. Then, select install zip from sdcard, then select choose zip from sdcard. Scroll to the Base_HTC_*.*.zip file on the SD card and select it. Confirm installation by selecting Yes on the next screen.
  16. NOTE: If installation of the Base_HTC file completes in less than 5 seconds, repeat step 15. Else, go to next step.
  17. After ROM installation completes, select choose zip from sdcard again, then select the *.*EndeavorU_Essentials.zip file, then confirm installation by selecting Yes.
  18. Again, after installation completes, select choose zip from sdcard again, then select the Slim_Gapps.zip file to install the Google apps package.
  19. After installation is complete, select go back then select reboot system now to reboot the phone and boot up into Slim ROM.

Slim ICS ROM is now installed on your HTC One X. Visit the official development page for more information and to get the latest updates on the ROM. Share your thoughts on the ROM in the comments below.