Big news for Xiaomi fans, especially for Mi Mix 2S owners. The company soon will release the latest Android 9 Pie update for the device. Meanwhile, MIUI 10 Global Beta ROM v8.8.28 based on Android 9 Pie is available for Xiaomi Mi Mix 2S that you can download and install right now and experience all the new goodies of Pie update before others get it.
Recently, Xiaomi invited Mi MIX 2S owners for testing Android 9 Pie based MIUI 10 Global Beta. The beta update is live for the device. If you would like to install the update manually, then you can download MIUI 10 Global Beta ROM v8.8.28 (Android 9 Pie) from below link and flash via stock recovery or TWRP.
As per the recent developments, the Mi MIX 2S probably will get Android 9.0 based stable MIUI 10 update before 2019. Redmi Note 5, Note 5 Pro, Redmi 6/6A, Mi Max 3, Mi Mix 2 and few other devices are also eligible for Pie update. These devices will get Android 9.0 based MIUI 10 Global Beta builds soon.
In this guide we show you how to install MIUI 10 Global Beta ROM v8.8.28 on Mi MIX 2S. The good news is that Xiaomi’s beta update is usually stable, which means it can be used as a daily driver. However, there might have unknown bugs that affect you.
Note that to install this ROM your device should be running on the latest MIUI Global Beta ROM. Before proceeding, backup all the content on the phone.
Install Android 9.0 Pie based on MIUI 10 Global Beta on Mi Mix 2S
1. Download MIUI 10 v8.8.28 Global Beta build for the Xiaomi Mi Mix 2S from here and transfer it on the phone.
2. Now, go to Settings > About phone > System Updates.
3. Tap on the option “Choose update package”.
4. Navigate to the zip file to flash it.
If above method does not worked, you may try it via TWRP. Boot your phone into TWRP and flash the ROM by selecting the ‘Install’ menu. Enjoy Android 9.0 Pie on your Mi Mix 2S. (source)