Xiaomi is one of the OEM who takes ages to roll out new Android updates. It has been over ten months since Android Nougat became official, but still, most of the Xiaomi devices run MIUI 8 based on Android Marshmallow. Xiaomi did release MIUI 8 update on top of Android Nougat for some phones such as Xiaomi Mi 5, Xiaomi Redmi Note 4 (Beta), but the disappointing fact is that the update misses out all the core Android Nougat features.
Xiaomi's MIUI 9 will be a major upgrade, which will be based on Android Nougat, but none of the devices has received it. And now, Xiaomi announces the MIUI 8 Developer Edition update for the users of Xiaomi Mi 5s, Mi 5s Plus, Mi Note 2 and Mi Mix. However, same as the Xiaomi Mi 5, the update is still MIUI 8
There won't be any visual changes in the new update, but the core elements of Android will be upgraded to Android Nougat. To update the MIUI 8 with core Android Nougat elements, Xiaomi has taken over ten months, which is underwhelming. However, it's already known that Xiaomi is working on the MIUI 9 which adds a slew of new features such as Picture in Picture mode, Multi-Window mode, and other Android Nougat features as well.
Nevertheless, the update is still a Developer Edition one, which means that the stable one will take few months to arrive. The update changelog is:
Add an upgrade to Android N, welcome to upgrade experience.
Lock screen, status bar, notification bar.
Fix the issue area of the notification bar does not appear.
Fix the correct password for the wrong question desktop.
Optimise the sliding response time.
Optimise loading speed (drastically reduce load time).
Fix the problem of recovery immediately after recovery.
In some cases, the icon does not show the problem.
Furthermore, the update is released only for the models mentioned above, and it should be installed by downloading the ROM manually. Users can find the Developer Edition MIUI 8 for Mi Note, Mi Mix, Mi 5s and Mi 5s Plus in the Mi Forums page. Also, do make a note that only the Chinese ROM is released, and it won't come with Google Apps installed. However, you can sideload the Google Apps with ease.