- Android 12 integrates the Android Runtime (ART) into Project Mainline.
- Google can issue ART upgrades to Android 12 devices through Google Play updates.
- This is good news for timely bug and security fixes without the long waits associated with full OS updates.
Despite arriving faster than in previous years, timely Android updates are still a bugbear of Google’s mobile ecosystem. Google started down the road to solving this problem with 2017’s Project Treble, this was then extended to enable component updates via Google Play with Project Mainline. Google is now extending the scope of Project Mainline in Android 12 to encompass the Android Runtime (ART).
The key takeaway is that Google is bypassing more and more of the update work that used to be done by third parties — such as silicon vendors and device manufacturers — and taking on the responsibility itself. Project Mainline allows components to be updated via Google Play, bypassing the need for a full Android upgrade to improve and secure parts of its operating system (OS). In other words, devices can be kept more secure and up to date quickly and easily, while major updates will also be faster to package and roll out.
Looking at Android 12 specifically, ART is responsible for turning the Java bytecode into native machine code to run on a processor. ART also handles app-level memory management and garbage collection. Integrating ART into Project Mainline means important ART-related bug and security fixes can be patched without the need to wait for device manufacturers and silicon vendors to get around to it. Google states this will allow the OS provider to “improve Runtime performance and correctness, manage memory more efficiently, and make Kotlin operations faster — all without requiring a full system update.” Google has also expanded the scope of other modules with Android 12, such as enabling its seamless transcoding feature via an updatable module.
Bringing ART into Project Mainline isn’t a complete game-changer for the way Android 12 will handles updates. Rather, this is simply one more component that Google is now able to update through the Play Store. This is great for keeping consumers up to date and lightens the workload for major Android OS upgrades. It’s also good news for third-party app developers, who will need to worry less about behavioral consistency across the Android ecosystem.
Of course, this is all providing that smartphone manufacturers support ART updates via Project Mainline. There’s no word from Google on whether this feature is mandatory in Android 12 or if it’s backward compatible with devices upgrading to its latest OS version. This could be a major drawback, as we’ve seen very few devices take up the ability to issue GPU driver updates over Google Play. Also, Android OS distributions that ship without Google Play — such as those in China or custom ROMs — can’t benefit from Project Mainline’s upgradeable modules.