The Sony Xperia ZL, which is currently running on official Android 4.1.2 Jelly Bean software version, can be upgraded to latest Android 4.2.2 using the nightly builds released by the Android Open Kang Project (AOKP) Team.

Sony Xperia ZL
AOKP JB-MR1 nightly builds are available for Xperia ZL. Sony

The AOKP JB-MR1 nightly build integrates several customised features and tweaks which are not found in the official firmware. Besides, the custom firmware fixes bug issues spotted in the previous release and brings performance improvements as well.

Xperia ZL users who wish to install Android 4.2.2 on their devices using AOKP JB-MR1 nightly, may follow our step-by-step guide. Users may come across minor bug issues with the installation of the nightly build since it is going through development phases.

IBTimes UK reminds its readers that it will not be held liable for any damage to the device. Users are also advised to verify that their handsets meet following requirements.

Pre-requisites

1) Install USB Driver for Sony Xperia ZL to transfer files between the Android device and computer.

2) Enable USB Debugging Mode on the phone to connect it with the computer and use Android SDK with it. [Press Menu>> Settings>> Applications. From there navigate and click on Development option and ensure the USB Debugging Mode is turned on.]

3) As the tutorial is likely wipe all data of the phone, create a back-up. If the device is having a custom recovery such as CWM/TWRP installed then backup data using the recovery mode.

4) The phone should be rooted and have ClockworkMod (CWM) recovery installed.

5) The bootloader of the phone should be unlocked.

6) The Xperia ZL should have 80 per cent of battery charge.

7) After flashing the ROM if the device gets stuck on Booting animation or experience boot loop then perform wipe cache partition and wipe dalvik cache five more times and then reboot the device.

8) Users are advised to give five to 10 minutes to the ROM once the device boots up for the first time to settle everything for a better user experience.

9) The AOKP JB-MR1 nightly build works only on Sony Xperia ZL, applying this on any incorrect variant might brick the device.

Steps to install Android 4.2.2 Jelly Bean AOKP JB-MR1 nightly build on Sony Xperia ZL

Step-1: Download Android 4.2.2 Jelly Bean AOKP JB-MR1 nightly build for Sony Xperia ZL to the computer

File name: aokp_odin_nightly_2013-05-24.zip [Alternative link]

Step-2: Download Google Apps package

Step-3: Connect the Xperia ZL to the computer using USB cable. Now copy both the downloaded zip files to the SD card of the phone

Note: Do not extract any file.

Step-4: Disconnect the phone from the computer and then switch it off

Step-5: Boot the phone into recovery mode. To do so reboot the phone and press the Volume Down button few times while booting

Note: In recovery mode, use the Volume keys to scroll between options and Power button to select the desired option.

Step-6: While the phone is in recovery mode, perform a Nandroid backup of the existing ROM which can be restored later if the new ROM does not work or users wish to go back to the previous firmware version. To perform a Nandroid backup, select Backup and Restore then on the next screen select Backup again. Once the action is completed, go back to the main recovery menu

Step-7: Now perform data wiping task to avoid clash between the new ROM and the previous build. To do so, select wipe data/factory reset then select Yes on the next screen to confirm the action. Wait for some time until the data wiping process is done. Now return to the main CWM recovery menu. Select wipe cache partition and after wiping cache partition process is over, select Wipe Dalvik Cache under advance option to perform Dalvik Cache wiping. After the process is done, go back to the recovery menu

Step-8: Select install zip from sdcard then select choose zip from sdcard. Now browse to the AOKP JB-MR1 build which was earlier copied to the SD card of the phone. Press the Power button to select it and confirm installation on the next screen. The ROM installation should begin now

Step-9: Once the ROM installation is completed, follow the same procedure (step-8) but now choose the Google apps file to install the same

Step-10: When the installation process is done, go back to the main recovery menu and reboot the phone by selecting reboot system now. The device will reboot now to boot up into the customised Jelly Bean ROM. The first boot will take about five minutes

As Sony Xperia ZL boots up, it should be updated with Android 4.2.2 Jelly Bean AOKP JB-MR1 nightly ROM. Head over to Settings>> About phone to verify the new software version running on the device.

Note: To go back to previous ROM, boot the Xperia ZL into recovery mode, select Backup and Restore then restore the ROM by selecting it from the list.

Click here for tutorial to root Sony Xperia Z on Android 4.2.2 Jelly Bean

[Source: Droid Firmwares]