Android at I/O 2019: The Project Mainline update system and other highlights

Here are a few highlights from the show.

Android’s gesture navigation is actually good now

Every Google I/O presents a new release of Android, and paired with Google I/O 2019 is Android Q Beta 3. There really aren’t a ton of changes in this beta release, but there is a new navigation system. There are three versions of system navigation in Android Q Beta 3, actually. The traditional three-button navigation is an option, even on devices like the Pixel 3, which originally did not ship with it. Apparently, the three-button mode will be returning to all phones for accessibility considerations, since the gesture system requires a significant amount of fine motor control. The existing Android Pie gesture system has been renamed “two-button navigation.” The third option, called “Fully gestural navigation, “is new for Android Q Beta 3, and it’s the best version of Android gesture navigation yet.

In Android P, the “two-button” gesture navigation was a bit of a mess. Google only replaced the Recent Apps button with a gesture, and Home and Back were still buttons. The bar didn’t save any space, so there wasn’t a huge benefit to using it. Beta three solves a lot of these problems. Every button is now a gesture. The navigation bar has been minimized to a slim strip about a third of the height of the usual bar. Some apps will even give you a fully transparent gesture navigation area. The new setup is very reminiscent of iOS, and that’s what everyone has been asking for since the launch of gesture navigation with Android P.

Let’s talk gestures. For “Home,” just swipe up from the bottom of the display. For “Recent Apps,” swipe up and hold. For “Back,” swipe in from either edge of the display. You can also switch between your last two apps by swiping up from the bottom and moving the app in an arc to the right. Again, it’s very iPhone-like, and a big improvement from the gesture system in Android P. The one non-iPhone gesture is really weird: a swipe up, diagonally, from the corner of the display, will open the Google Assistant. This one is completely undiscoverable.

There are a few strange edge-cases with the gesture system currently. First, trying to open Recent Apps from the Home Screen is a bit clunky. The swipe-and-hold gesture is strange to begin with (even on an iPhone), but on the home screen a swipe up also opens the app drawer. Trying to open Recent apps on the home screen means you will actually start raising the app drawer up from the bottom of the screen and bring the Recent Apps carousel in from the side of the screen . I think the home screen design needs to change if we’re going with this swipe-up system gesture.

The new gesture system means the system UI now captures touch input from the sides and bottom of the display, taking it away from apps. This will cause problems with some apps that have side-mounted controls, and to help with that, Google will introduce a new API allowing developers to reclaim touch input from the system. Developers can basically draw rectangles on the display to reclaim touch input, and Google recommends blocking out system-gesture input around things like seek bars.

The side navigation panel has been a common UI style for Android apps, and since many implementations open with a swipe in from the side of the screen, this will be the most common action that is disrupted by the new system gestures.

The word from Google I/O is that Google plans to fix this issue by changing the side navigation widget it provides to developers. With the new version, the first side swipe will open the navigation panel, and the second swipe will go back. The one app that implements this right now is the Google I/O app, and it’s pretty weird in practice. The first swipe back gets eaten by the app drawer, and only the second switch back will actually go back. The good news is that this only happens on the main page of the I/O app. If you do something like open an I/O session and swipe, you will immediately go back. I think the best solution is to try to not use a navigation drawer, which has been derided in the past as being a dumping ground for navigation with poor discoverability.

The other oddity is that this new behavior will only apply to apps with the updated navigation panel, so you’ll have inconsistent behavior depending on if the app is running the new side panel widget or not.

The fully gestural navigation system covers “Home,” “Recent Apps,” and “Back,” but the Android system bar contained more than just these three buttons at times. When you opened a keyboard, the back button would change to point down, indicating that instead of going back, the button would just close the keyboard. This icon doesn’t fit in the slimmer gesture bar, so now when a keyboard is open, the gesture bar actually grows to the old size, and then it has room to display the old button. The other missing button from the new bar is Android 9 Pie’s smart rotation switch, which just never shows up anymore.

Visually, there are a few compatibility quirks, too. First, let’s look at the best case scenario and open something like the Google I/O app on Android Q Beta 3. This is the Android gesture system at its full capabilities, with a fully transparent system bar that the current app can draw behind. In the IO app, you only see the thin gesture line and nothing else, just like an iPhone X. Android will even continuously sample the background as you scroll. It will smoothly fade between a dark and light themed gesture bar to maintain contrast.

Most apps don’t look like the Google IO app, though, and instead of a beautiful, transparent gesture area, you get a regular black or white Android system bar that is segmented away from the rest of the app. Apps that don’t request a transparent system bar get this older-looking, uglier gesture bar, so uh, please update your apps, everyone on Earth.

Another major navigation change Google showed off at I/O had to do with the “Next Generation Google Assistant.” This was a turbocharged assistant with offline functionality and lots of natural language processing. The next-gen Assistant demo used the old two-button gesture navigation system, and in the blank spot where “Recent Apps” used to be, the next-gen Assistant would transcribe your voice input.

The demoed next-gen assistant UI is totally incompatible with the future of where Android is going. The full gesture system in Android Q doesn’t have a blank spot to use for voice transcription—the slimmer bar isn’t even tall enough to fit a single line of text. This is just not going to work as shown at Google I/O. Did the Google Assistant team not talk to the Android Team or something?

Project Treble is making a difference

Starting with Android 8.0 Oreo and finishing up in Android 9 Pie, Google introduced “Project Treble” a modularization of Android that separated the OS from the hardware support. Treble was a scheme to make Android updates less work to build and easier to update, and there were signs all over Google I/O 2019 that Treble is actually making a difference.

Just like last year, later Android betas are now available on non-Google phones, but this year the list is bigger than ever. Android Q Beta 3 is coming to 23 devices, with 15 from third-party OEMs.

This list shows that most important Android manufacturers are now taking part in the Android Q Beta. The only heavy hitters missing are Samsung—which is pretty much always hostile to consistency and cooperation within the Android ecosystem—and Lenovorola, another company that doesn’t care about Android updates.

It’s not just that these devices were announced as compatible for the Android Q beta—some of them were on display at I/O, and they were shockingly far along. Huawei had the Mate 20 Pro on display and it was actually . Huawei’s Android skin, EMUI, is a heavy, full-conversion of Android, and to see that it was already working on a beta was a real shock. Unfortunately, Huawei won’t be able to finish its Android Q development, as a US executive order has banned companies from doing business with the Chinese company. The Mate 20 Pro used to be on the Android Beta page, but after the order, it was quietly removed.

Project Treble is making a difference on the retail side of things, too. In a post on the Android Developer Blog, Google said Project Treble “accelerated Android 9 Pie OS adoption by 2.5x compared to Android Oreo.” Faster is always better, but with 2.5 billion active devices (another new stat just announced by Google) getting anything to change is like turning the Titanic. The Android Platform Dashboard is back after about a six-month hiatus, and we can see that Pie currently makes up just 10 percent of the current Android active user base. Still, there are 250 million Android 9 Pie devices out there.