On March 21, Google released the first of their planned Android O developer previews. Here’s a quick guide to being excited about it.
New Typographic Features
Custom fonts will now be supported natively. No need to use third party libraries (like Calligraphy) anymore. Until Google brings it to the support library as well, that is.
Making your TextViews shrink or expand, depending on device's screen size, just got faster and less hacky.
[Full justification](https://developer.android.com/reference/android/widget/TextView.html#setJustify(boolean)
No more fiddling around with WebViews to achieve full justification. Which, per se, has its own disadvantages.
Java 8 API For Date And Time And More
Existing Java date and time classes are bug-prone, counter-intuitive and not thread safe. New java.time, designed in collaboration with the author of life-saving Joda-Time, deals with these problems in JDK core.
And here's a comprehensive list of new Java APIs being added to Android O.
No Need To Cast The Returned View Anymore
Less boilerplate. If you're not already using Butterknife, that is.
Adaptive icons can display a variety of shapes across different devices' models and OEMs. The mask, that the icon will be rendered to, will be provided by the operating system. Adaptive icons will support various visual effects of user interaction (zoom, bounce, outline etc.) They will also be used for shortcuts, the Settings app, sharing dialogs and the overview screen.
All this will allow your Android home screen to be more visually consistent (no more bazillion icon shapes).
A GIF explains more than a thousand words, so here it goes:
If your hands are itching to try it out, there are already some free resources available to get you started.
Better Color Support
Design geeks that see more colors than most of the mortals should now be happier. Color support on Android is really going places. As per this article:
Image color space will not be limited to sRGB only and applications will be able to display Adobe RGB, ProPhoto RGB and other color spaces properly.
Well, it's pretty and now easily available on Android. You won't need to waste any more time talking the dev team into it.
Background Limits
Seems Google is hard at work, trying to save devices' RAM and battery life. Starting from Android O, there will be more automatic limits on what apps can do in the background.
Picture-In-Picture
tl;dr You'll now be able to watch Youtube videos while doing other stuff on your phone.
Notifications Redesigned
Notifications can now be grouped into categories and dealt with either individually or in a bulk.
Autofill API
Autofill will now be supported by platform and users will be able to choose their autofill app similarily to keyboard app.
Of course, that's not all Android O has to offer. You can learn more from Android Developers blog and developers.android.com. If you're a developer, you can find a bunch of interesting information here, as well as consult the API difference list here.