Google announced Project Treble last year in an effort to revamp the way device makers update their smartphones. Phones launched with Android Oreo are required to be compatible, but it's optional for OEMs to include Treble support with Oreo updates for older smartphones. One potential benefit of Treble support is that major software updates can arrive faster for devices that support it, as device makers can pursue updating the Android framework without waiting on a vendor to update their code. Thanks to Project Treble's requirements, though, every device that supports it must be able to boot a generic build of AOSP, which makes bringing AOSP to certain devices like the Honor 8 Pro or Honor 9 a lot easier.

In November, we showed you how Project Treble enabled developers to create a single system image that boots on multiple devices. Devices such as the Huawei Mate 9 could now run AOSP Android Oreo, a thing which had not been achieved before. Huawei has been leading Android OEMs when it comes to supporting Project Treble, as the company has included Treble support in all of their Oreo updates (which are still ongoing). Devices that already came with Android Oreo and thus are Treble-compatible out of the box such as the Huawei Mate 10 Pro can also easily run AOSP Android Oreo.

Now, XDA Recognized Contributor surdu_petru has released OpenKirin's AOSP Android Oreo for the Honor 9, and XDA Recognized Developer OldDroid has released the same for the Honor 8 Pro. OpenKirin is a well-known team of ROM developers for Huawei/Honor devices, and what's notable about this ROM is that it is based off of a generic build of AOSP which is possible thanks to Project Treble.

The AOSP Treble Oreo custom ROMs are basically barebone AOSP as of now with the superuser binaries already included—users just need to install the SuperUser app by XDA Senior Member phhusson to enable superuser access. It also comes with the stock EMUI camera which was modified by phhusson to get it working, and although most of the stock camera features work, some may not. Fingerprint gestures, the Google Pixel animations, XPe Browser, and Nano Gapps are also included.

So what's broken? Not much, actually. The only issue listed in the developers' threads is that the 2G/3G signal bars will always show at full strength. Furthermore, you won't be passing SafetyNet on this build so no Android Pay unfortunately. Still, for a first release of an AOSP build on a device, it's pretty impressive that so much works already. But that's the magic of Project Treble for you. Here's how to install the build onto your phone.

How to install the AOSP Android Oreo ROM on the Honor 8 Pro and Honor 9

The following instructions are fairly brief since you should already be somewhat comfortable with modifying your device before you attempt flashing this.

  1. This first step is very, very important: you must already be running the EMUI 8/Android Oreo update. You can follow this guide for the Honor 9 or this guide for the Honor 8 Pro if you haven't received the update already.
  2. Unlock the bootloader of your device.
    1. Request an unlock code here
    2. Go to Developer Options and enable USB Debugging
    3. Setup ADB and Fastboot binaries on your PC.
    4. Reboot into fastboot mode, and then enter fastboot oem unlock [code] in a command prompt or terminal.
  3. Download the Treble ROM zip from the respective thread and unzip it. Go here for the Honor 8 Pro and here for the Honor 9.
  4. Reboot to bootloader.
  5. Open a command prompt or terminal in the directory where you unzipped the file and enter the following command: fastboot flash system system.img
  6. Enter the stock recovery and do a factory reset.

After you do this, you should boot up into an AOSP build of Android Oreo on your Honor 8 Pro and Honor 9. Now, AOSP doesn't have much to offer in terms of features and these ROMs are primarily focused on stability first, so you'll be missing quite a bit of features. To help with that, here are a few tips.

What to do after installing a Treble ROM

I recommend that you install the following apps:

Substratum should cover all of your theming needs while the Xposed Framework and GravityBox should give you most of the custom ROM features that you are missing. Things like Night Light, Adaptive Brightness, and Ambient Display are being worked on at the moment since they require an RRO framework overlay installed in /vendor, but it shouldn't be long before that's available. In the meanwhile, you can install apps such as Lux, CF.lumen, and ACDisplay to replicate those functions.

The GravityBox Xposed Module offers enough features to replace a custom ROM

If you are interested in keeping up with all of the latest developments related to Project Treble, then take a look at our dedicated forum for this topic down below.

Check out our Project Treble Development Forum