You may now upgrade Sony Xperia U to Android 4.4 KitKat using an unofficial CyanogenMod 11. It features bloatware-free system and tweaks exclusive from CyanogenMod ROMs.

CyanogenMod 11

Owners of Sony Xperia U can now flash the CyanogenMod 11 via manual procedure and can enjoy bloatware-free system and tweaks added by the developers.

Here are some notable changes and fixes on the CM 11 for Xperia Sola:

- Updated kernel version

- Updated CM11 sources

- Wi-Fi and tethering

- Microphone and audio output

Requirements

1. Manually backup all data files and personal information stored on your smartphone.

2. Make sure that the battery level is at least 75 per cent.

3. Unlock the boot loader of your smartphone via Sony's official unlocking procedure.

4. Download and install a custom recovery tool on your Xperia U. Click here to know how.

5. Download and install the ADB tool kit on your computer.

6. Enable USB debugging mode on your smartphone. Go to "Settings > Development > USB debugging mode."

7. Download the fastboot zip files to your computer.

8. Download the CyanogenMod 11 and Google Apps package to your computer.

Warning: CyanogenMod 11 requires manual installation that can damage your smartphone. IBTimes and developers of CyanogenMod are not responsible for any errors which may occur on your Xperia U. Read, understand and follow the instructions to avoid damaging your device. Do this at your own risk!

Flashing Instructions

1. Extract the fastboot files you've downloaded to a folder on your computer desktop.

2. Unzip the Xperia U CM11 firmware which contains the "boot.img" kernel file then save it to the fastboot folder.

3. Connect your Xperia U smartphone to the computer using a USB cable.

4. Copy and paste the CM11 and Google Apps package to the SD card of the Xperia U.

5. Disconnect the smartphone from your computer then turn it off.

6. Press and hold the 'volume up' key while you connect the smartphone to the computer using a USB cable.

7. Once your phone LED turns blue, open the fastboot folder on your computer.

8. Launch a 'command window' inside the fastboot folder.

9. Type the following commands: fastboot flash boot boot.img

10. Once the 'finished' message appears, disconnect the phone from the computer then turn it on while pressing the 'volume down' key continuously.

11. Inside the recovery mode, select "backup and restore > backup" to save a copy of the current ROM. You may restore the saved ROM anytime.

12. Perform a full wipe by selecting "wipe data/factory reset" and "wipe cache partition" then "advanced > wipe Dalvik cache."

13. Install the CyanogenMod 11 by selecting "install zip from SD card > choose zip from SD card > find the CM11 firmware > confirm installation." Apply the same with the Google Apps package.

14. Once the installation has been completed, go back to the main menu and select "reboot system now."

15. Sony Xperia U will reboot and may take up to five minutes before reaching the home screen.

For any comments or issues, send your feedback to XDA developer main thread of Sony Xperia U Android 4.4 KitKat custom ROM.