So I did something dumb yesterday afternoon. Google put out the factory images for the Android L Developer Preview on Thursday, right on the heels of the I/O keynote, and I had my Nexus 5 flashed and rebooting before I'd even finished my coffee. In hindsight I should've read more than the first paragraph of the instructions.
Quick context if you missed the keynote (I watched about forty minutes of the livestream on a work laptop with the sound off, which is basically how everyone watches I/O). Google's calling the new design language "Material Design" — cards, bold color blocks, shadows that are supposed to mimic actual sheets of paper stacked on top of each other. It's a real visual departure from Holo, which has looked kind of tired since about 2012 if I'm honest. There's also a new runtime under the hood, ART, which replaces Dalvik as the default instead of being the opt-in experiment it's been since KitKat. Google's claiming better performance and battery life. We'll see.
Anyway. The images are up on the Android developer site for Nexus 5 (hammerhead) and the 2013 Nexus 7 Wi-Fi (razor), and the process is the usual fastboot dance: unlock the bootloader if it isn't already, adb reboot bootloader, then run flash-all.sh from the extracted folder. Takes maybe ten minutes including the reboot. What the download page does not make especially loud is that this wipes your device completely. Not "backs up and restores," not "keeps your apps." Wipes it. I lost about three weeks of texts because I didn't think to export them first, which is entirely my own fault but also the kind of thing I wish had a bigger warning label than one line of gray text.
First impressions, since you're probably wondering if it's worth doing to your own daily phone (short answer: no, not your daily phone):
- The lock screen now shows notifications directly, and you can double-tap one to jump straight into the app. Small thing, saves a step, I like it.
- Quick Settings and the notification shade have been redesigned and honestly look a little unfinished right now, some icons are misaligned, a couple of toggles just don't do anything yet.
- Recent Apps is a proper vertical stack of cards now instead of the old horizontal thumbnail strip. Feels more like it belongs with everything else Google showed off.
- My battery went from lasting a full day to needing a top-up by 4pm. This is a developer preview running on a phone that's over a year old at this point, so I'm not reading too much into it, but it's worth saying plainly: don't flash this onto the phone you actually need.
- Hangouts crashed on launch three separate times before I gave up trying to send a text through it. Ended up falling back to the stock Messaging app, which at least opened.
I was doing all of this with the World Cup on in the background, which felt weirdly appropriate — the US lost to Germany 1-0 on Thursday and everyone I know was more upset about a soccer match than I've seen Americans get about soccer in years, and meanwhile I'm sitting there watching a boot animation loop because I messed up a partition somehow on my first flash attempt. Had to fastboot the whole thing again. Turns out advancing to the knockout round on goal difference despite losing is a very strange kind of good news, and so is a developer preview that occasionally forgets how to render the settings menu.
If you want to try this yourself, a few honest recommendations. Use a spare device, not your primary phone. I cannot stress this enough after losing those texts. Back up anything you care about the old-fashioned way, copy photos off manually, don't trust that Google's sync will catch everything before you wipe. And go in expecting rough edges, because this is very obviously not a finished build; app compatibility is spotty, some third-party apps just force-close on ART instead of Dalvik, and Google hasn't said anything yet about a public release timeline, just "later this year."
Material Design itself, the parts of it that are actually implemented so far, is a nice enough shift. Whether it holds up once every app on the Play Store starts trying to imitate it is a different question, and I've got a feeling we're going to see a lot of cards and drop shadows slapped onto things that don't need them for a while. That's usually how these things go.