Fresher OS with Projects Treble and Mainline

Posted by Anwar Ghuloum, Engineering Director and Maya Ben Ari, Product Manager, Android

With each new OS release, we are making efforts to deliver the latest OS improvements to more Android devices.

Thanks to Project Treble and our continuous collaboration with silicon manufacturers and OEM partners, we have improved the overall quality of the ecosystem and accelerated Android 9 Pie OS adoption by 2.5x compared to Android Oreo. Moreover, Android security updates continue to reach more users, with an 84% increase in devices receiving security updates in Q4, when compared to a year before.

This year, we have increased our overall beta program reach to 15 devices, in addition to Pixel, Pixel 2 and Pixel 3/3a running Android Q beta: Huawei Mate 20 Pro, LGE G8, Sony Xperia XZ3, OPPO Reno, Vivo X27, Vivo NEX S, Vivo NEX A, OnePlus 6T, Xiaomi Mi Mix 3 5G, Xiaomi Mi 9, Realme 3 Pro, Asus Zenfone 5z, Nokia 8.1, Tecno Spark 3 Pro, and Essential PH-1.

But our work hasn’t stopped there. We are continuing to invest in efforts to make Android updates available across the ecosystem.

Safer and more secure devices with Project Mainline

Project Mainline builds on our investment in Treble to simplify and expedite how we deliver updates to the Android ecosystem. Project Mainline enables us to update core OS components in a way that's similar to the way we update apps: through Google Play. With this approach we can deliver selected AOSP components faster, and for a longer period of time – without needing a full OTA update from your phone manufacturer. Mainline components are still open sourced. We are closely collaborating with our partners for code contribution and for testing, e.g., for the initial set of Mainline components our partners contributed many changes and collaborated with us to ensure they ran well on their devices.

Project Mainline updates via Google Play infrastructure components in the Android OS Framework. The Framework components updated are located above the Treble Interface and Hardware-specific implementation, and below the Apps layer.

As a result, we can accelerate the delivery of security fixes, privacy enhancements, and consistency improvements across the ecosystem.

Project Mainline has security, privacy and consistency benefits. Security: Accelerate pushes and remove OEM dependency for critical security bugs. Privacy: Better protection for user’s data; increased privacy standards. Consistency: Device stability and compatibility; developer consistency.

Security: With Project Mainline, we can deliver faster security fixes for critical security bugs. For example, by modularizing media components, which accounted for nearly 40% of recently patched vulnerabilities, and by allowing us to update Conscrypt, the Java Security Provider, Project Mainline will make your device safer.

Privacy: Privacy has been a major focus for us, and we are putting a lot of effort into better protecting users’ data and increasing privacy standards. With Project Mainline, we have the ability to make improvements to our permissions systems to safeguard user data.

Consistency: Project Mainline helps us quickly address issues affecting device stability, compatibility, and developer consistency. We are standardizing time-zone data across devices. Also, we are delivering a new OpenGL driver implementation, ANGLE, designed to help decrease device-specific issues encountered by game developers.

Our initial set of components supported on devices launching on Android Q:

Security: Media Codecs, Media Framework Components, DNS Resolver, Conscrypt
Privacy: Documents UI, Permission Controller, ExtServices
Consistency: Timezone data, ANGLE (developers opt-in), Module Metadata, Networking components, Captive Portal Login, Network Permission Configuration

How does this work?

Mainline components are delivered as either APK or APEX files. APEX is a new file format we developed, similar to APK but with the fundamental difference that APEX is loaded much earlier in the booting process. As a result, important security and performance improvements that previously needed to be part of full OS updates can be downloaded and installed as easily as an app update. To ensure updates are delivered safely, we also built new failsafe mechanisms and enhanced test processes. We are also closely collaborating with our partners to ensure devices are thoroughly tested.

APEX file format. At the top level, an APEX file is a zip file in which files are stored uncompressed. The four files in an APEX file are: apex_manifest.json, AndroidManifest.xml, Apex_payload.img, apex_pubkey

Project Mainline enables us to keep the OS on devices fresher, improve consistency, and bring the latest AOSP code to users faster. Users will get these critical fixes and enhancements without having to take a full operating system update. We look forward to extending the program with our OEM partners through our joint work on mainline AOSP.