Besides Android 7.0 Nougat native features, MIUI 8.5.4.0 Global Stable ROM brings separate app lock for Dual apps, hides notification content on the lock screen, support exFAT file system for SD card, offers improved Google keyboard, more customizable quick settings menu, and more. The update also includes general bug fixes and several optimizations.

Note that, Redmi Note 4/4x will get the more refined MIUI 9 Beta 7.8 update soon. It is scheduled for August 11. Check this guide for download and installation instruction. MIUI 8.5.4.0 Global Stable ROM update weighs around 1.3GB and currently rolling out in few countries. However, all Redmi Note 4/4X will get the OTA (over the air) update within a week or more.

How to download and install MIUI 8.5.4.0 Global Stable ROM on Redmi 4.4X

  1. MIUI 8.5.4.0 Global Stable recovery ROM zip files from here.
  2. Rename the ROM to update.zip and save it on your phone.
  3. Turn off your phone and then press the Volume + button along with the power button to boot into Mi Recovery.
  4. Navigate to update.zip file (use Vol up/down button and select it using power button).
  5. Confirm the installation by selecting the Yes button. Once it is installed then selects the back button and then reboot. After installation, setup and enjoy new Android version. Any question? Leave it in the comment section below. (Source)