Sony Xperia Z3 Owners, follow the step by step tutorial to update Xperia Z4 to Android 5.1.1 Lollipop, thanks to Cyanogen Mod 12.1 (CM12.1) custom ROM.
- First of all, make sure your Xperia Z3 is fully charged.
- Keep backup of all your important data.
- Enable USB Debudding on your phone.
How to Update Xperia Z3 to Android 5.1.1 Lollipop Using CM12.1
Step 1: Download the CM12.1 Android 5.1.1 Lollipop Custom ROM and GAPPS for your Xperia Z3 using above links and place the zip files on desktop.
Step 2: Connect your Xperia Z3 to your computer and transfer the download zip files to your phone SD card.
Step 3: Turn Off your phone and boot it to recovery mode.
Step 4: In recovery mode, first tap on “wipe data factory reset” option to perform a factory reset. Once this is completed, go to advanced options and select “wipe the cache” followed by “dalvik cache” options to clear the cache.
Step 5: Go back to main recovery menu and select “Install zip from sd card” followed by “choose zip from SD card” and select the ROM zip file you have transferred to SD card earlier.
Step 6: Once custom ROM is flashed, use the step 5 again to install Google Apps (GAPPS)
Step 7: Once the installation is completed, go back to main recovery menu and reboot your phone which might take few extra minutes for first reboot, so don’t be panic.
This is it.