A series of Xperia devices can be updated to Android 6.0 Marshmallow. No, not through official updates by Sony but through custom ROMs created by developers. And no, they are not the latest Sony devices like the Xperia Z3 or Xperia Z2, they are older.
If you are a Sony Xperia Z1, Xperia Z1 Compact or an Xperia Z Ultra owner, then you can update from whatever Android version your phone is to Marshmallow. And all this thanks to devoted developers who have made this possible.
Of course, the AOSP Marshmallow ROM is not stable. It it in beta stage which means there are many things which are not working and might take a long time to get fixed. After all, it will take a long time, probably months for any of these devices to see an official Marshmallow update from Sony. So this AOSP ROM is a good way to see how Android 6.0 works and performs on older devices.
How to install AOSP Marshmallow ROM on Xperia Z1, Z1 Compact & Z Ultra
Each ROM download contains four files that you need to download: boot.img, cache.img, system.img, userdata.img.
- Install the ADB drivers so your phone can communicate with the computer. Also, go to Settings > Developer Options and enable USB Debugging.
- Download all four required files and move them to the ADB folder for easier access.
- Grab your phone and turn it off and boot into fastboot mode (volume up + power button). Once you press the volume up button, connect your phone to your computer with a USB cable.
- Now go to the ADB folder, press shift and right-click with your mouse and select Open Command Window here.
- Now you need to run four commands to flash all four files that you downloaded.
- The first command:
fastboot flash boot boot.img
- Then run:
fastboot flash cache cache.img
- And then:
fastboot flash system system.img
- And finally:
fastboot flash userdata userdata.img
- Now reboot your phone and wait for it to boot up. You will be greeted with the stock Marshmallow home screen. Now, if you want to root your phone, you need to move the SuperSU file to your phone and then power it off.
- Boot into recovery mode, wipe cache and flash the SuperSU file.
Now your Xperia Z1, Z1 Compact or Z Ultra will be running on the latest rooted Marshmallow ROM.