At Google I/O, we finally got a good look at Android 12 and its new lock screen, notifications and color redesign. Here’s what to know.

Google’s Android 12 operating system, fully unveiled at the Google I/O developer conference Tuesday, represents the biggest design change in the history of the OS, complete with personalizable color palettes, updated notifications and faster, battery-saving performance.

There are now more than 3 billion active Android devices worldwide, Sameer Samat, vice president of Android, said during the Google I/O keynote. Now available as a public beta (here’s how to download Android 12) and with a general release likely arriving around September, Android 12’s new features may differ depending on your device. On Google Pixel phones, when you choose your wallpaper, a feature called color extraction will update the whole system, including your lock screen, widgets and notifications, with custom complementary colors, Samat said.

Another part of the redesign involves more fluid motions, animations and responses to your touch. You’ll find an always-on display, and more adaptive notifications — for example, when you dismiss them on the lock screen, the clock will appear larger, so you know you’re caught up.

Several under-the-hood improvements promise to speed up your phone and save battery life, including reducing the CPU time needed for core system services by up to 22% and reducing the use of big cores by the system server by up to 15%, Samat said.

Notifications also get a refresh to give you a better at-a-glance view. The Quick Settings bar also gets an update, and now includes Google Pay and Home Controls along with more customization so you can keep everything you need in one place that’s easy to access.

When you press the power button, you’ll trigger Google Assistant for helping to make phone calls, asking questions or reading articles aloud.