Very good news for Sony Xperia M4 Aqua as the unofficial AOSP Android 7.1.1 Nougat custom ROM is available for this device. You can easily download the firmware files from the below download section or you can download from the XDA page. Xperia M4 Android 7.1.1
AOSP is one of the oldest custom ROM project which produces custom ROMs for almost every android device, just like CyanogenMod or Lineage, AOSP ROM also had gained a lot of reputation and a great feedback from their users. Xperia M4 Android 7.1.1
This is unofficial Android 7.1.1 update so you may not get all OTA update but the best part is that you can enjoy Android Nougat Features and Android 7.1.1 is latest Android nougat version and you will get it from our guide this method require custom recovery like TWRP or CWM installed on your android device and backup is must because in this process all you data will be lost. Follow this guide to safely Update your Ulefone Metal to Android 7.1.1 Nougat via Unofficial AOSP 7.1.1.
Special thanks to Cubbins
Sony Xperia M4 Aqua E2303 → Download Link
Sony Xperia M4 Aqua E2306 → Download Link
Sony Xperia M4 Aqua E2312 → Download Link
Sony Xperia M4 Aqua E2333 → Download Link
Sony Xperia M4 Aqua E2353 → Download Link
If you have any queries regarding this, feel free to ask in the comment sections.