CustomDroid
Xiaomi

Xiaomi MI9

Qualcomm Snapdragon 855 (SM8150)released 2019up to android 16latest android is 17
ro.product.devicecepheus

also sold as MI 9

Xiaomi MI9
photo: PixelExperience
Actively maintained

Released 2019, newest ROM build 1 week ago (4 ROMs still current). A phone that still gets updates keeps going long after its manufacturer stops.

Hardware

SoC
Qualcomm Snapdragon 855 (SM8150)
CPU
Octa-core (1x2.84GHz Kryo 485 + 3x2.42GHz Kryo 485 + 4x1.78GHz Kryo 485)
GPU
Adreno 640
Architecture
arm64
RAM
6/8 GB
Storage
64/128/256 GB
Screen
2340x1080
Released
2019

Specs from postmarketOS wiki (CC BY-SA 4.0).

ROMs · 08

The Xiaomi MI9 (codename cepheus) has 8 tracked custom ROMs on CustomDroid — including crDroid, iodéOS, Kali NetHunter and 5 more, running up to Android 16. Each listing links to the project's own download and install guide, and was last checked against the projects' catalogues on 21 Sept 2026.

Tick “compare” on two or three builds to see them side by side.

Show
Android

RSS feed — subscribe to get new Xiaomi MI9 builds in your reader · JSON

Before you flash

Flashing generally means unlocking the bootloader, booting a custom recovery, wiping, then installing the ROM. Exact steps differ per device and ROM, so follow the Install guide for the one you pick, and back up first. Check what can break (banking apps, DRM, carrier features) and how to get back to stock before you start. Why flash a custom ROM · All guides

Custom recovery for this device: TWRP. Flash the one your chosen ROM's guide asks for — common recovery errors.

This is a Qualcomm device, so on Windows you'll want the Google USB Driver (and QDLoader 9008 to unbrick) before your computer will see it in fastboot. Which USB drivers you need.

Timeline

  1. Jul 2026
    crDroid, Evolution X, PixelOS, Project Matrixx, RisingOS Revived first tracked
  2. Sept 2026
    PixelExperience, iodéOS, Kali NetHunter first tracked

Dates show when CustomDroid first indexed each ROM for this device, not when support originally launched.

ROM availability and links come from each project. CustomDroid indexes builds, it doesn't mirror them — always download from the official project, verify the file's hash/signature, confirm it matches your exact codename, and back up before flashing.