The Xiaomi Redmi Note 4, Redmi 4, Mi 3, and Mi 4 smartphones have unofficially received a port of Android 9 Pie. While the ROM for the Redmi Note 4 seems to have almost no bugs and is pretty stable, some bugs have been reported for the other three devices. Google recently announced the final build of its highly anticipated Android operating system and it is currently available for some select devices. However, abhishek987 and vasishath are two XDA Senior Members, who have successfully ported the latest Android 9 Pie OS for the Xiaomi Redmi Note 4 and the Mi 3/Mi 4 respectively. The Android Pie port for Redmi 4 was developed by the XDA Member hemantac.
The support thread of the Redmi Note 4 Android 9 Pie ROM suggests there are negligible bugs if it’s flashed as per the provided instructions. You can check out the thread for the Redmi Note 4 here and for the Redmi 4 here. As the Mi 3 and the Mi 4 share a common device code, the same ROM works for both of them and can be found here.
As all the above-mentioned ROMs are an early port, one generally expects some functionalities to be missing. However, all the major features of Android 9 Pie are said to be working for the Redmi Note 4 after flashing the ROM, but the developer says that there could be some yet to be discovered bugs and there is a known issue with hardware encryption. For the Mi 3 and the Mi 4, the only noted major bug as of now is users being unable to increase or decrease volume when listening to audio via headphones.
Those who are interested can go through the ROM flashing instructions on the respective threads and experience the latest Android 9 Pie on their Xiaomi devices. However, do keep in mind that as all ROMs are ported using the AOSP source code and thus the handsets will get stock Android interface without MIUI.
As per Xiaomi, the Redmi Note 4 was a huge success as the company sold over 1 million units in 45 days. Even though the smartphone was launched in India in February last year, it is still a decent option, owing to the hardware it runs on. It was launched running on Android 6.0 Marshmallow and last major update it received was of Android 7.0 Nougat. Now, it has unofficially received the Android 9.0 Pie port. Chances are slim that the device will be updated to Android Oreo as there is no confirmation from Xiaomi. Same can be said for the Xiaomi Mi 3 and the Mi 4, which were released in 2013 and 2014 respectively.