Sony Xperia Arc, Arc S and Pro are all compatible with Android 4.4 KitKat and firmware has been made available to each smartphone. Owners can now enjoy several improvements including features from Android 4.2 and Android 4.3 Jelly Bean.

CyanogenMod 11 via LegacyXperia

LegacyXperia Project is now offering unofficial builds of CyanogenMod 11 for legacy Sony Ericsson msm7x30 devices and it includes Xperia Arc, Arc S and Pro. Here is the status of CM11.0 with kernel 3.4:

- LCD and touch response

- SMS/MMS

- Accelerometer, proximity, ambient light, vibration

- Headphones, audio output

- Notification LED

- SD card

- USB Mass storage, MTP, PTP, ADB, OTG, tethering

- Camera, video recording, panorama

- Flashlight with red-eye mode

- Bluetooth music, calling, tethering

- Offline charging

However, there are known bug issues with the current release of CM11 for Legacy Xperia smartphones such as Wi-Fi functionality and screen-off animation. Other problems are classified as not working in 720p video recording, FM radio having no audio output, HDMI and Wi-Fi hotspot.

Requirements

1. Create a manual backup of all data files on your Xperia Arc, Arc S and Pro.

2. Make sure that the battery level is at least 75 per cent to avoid power interruption during the flash.

3. Unlock phone's boot loader via Sony's official unlocking procedure.

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

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

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

7. Download the fastboot zip files to your computer.

8. Download Android 4.4 KitKat CM 11 and the Google Apps package to your computer. Click on the model name for the appropriate firmware.

a. Xperia Arc/Arc S

b. Xperia Pro

Warning: CyanogenMod 11 from LegacyXperia Project is a custom-based built ROM. Manual flashing of firmware may damage your device and IBT Media or developers are not responsible for any errors which may happen. Read, understand and follow the instructions carefully to prevent errors to occur. Do this at your risk.

Flashing Instructions

1. Unzip the fastboot files and extract it to a folder on your computer desktop.

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

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

4. Copy and paste the CM11 and Google Apps zip files to the SD card of your smartphone.

5. Disconnect the smartphone from your computer and then switch 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. Open 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 and 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" and 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. Your Xperia smartphone will reboot and may take up to 5 minutes before reaching the home screen.

For any comments or issues, send your feedback Xperia Arc/Arc S/Pro XDA developer original thread.