Recently the Popular Redmi Note 4 has received MIUI 9.2.1. Which changes the overall user experience of the device. It also makes the device superfluid.
The Update is 420 MB in size. This update has the following components:-
1. MIUI 9.2.1
2. December Android Security Patch (5 December 2017)
3. Has some performance improvements under the hood.
To update your device go to Settings -> About Phone -> System Updates

Now hoping that Xiaomi would also release the latest Android Oreo for the Redmi Note 4.

Xiaomi Redmi Note 4 Update
-> Settings Page

Xiaomi Redmi Note 4 MIUI 9
->Major UI changes and addition of Mi Video Application