Of all the features that come with Android Oreo, the new Picture in Picture mode is possibly the biggest one we can see. The idea isn't exactly new (Samsung's had something similar for years) but Google added it at the system level in Nougat for Android TV, then for everyone — phones and tablets — in Android 8.0 Oreo so we would no longer need third-party solutions and a few lines of code can make it happen for everyone.
Adoption of the feature isn't what we would call widespread, at least right now. Very few phones have access to Oreo so the demand isn't there just yet. That will change in due time. Some developers are getting out ahead of the demand, though. We'll keep updating this list as more apps that support the new feature hit Google Play.
Hi: This list is up-to-date as of November 3, 2017.
VLC for Android
VLC is an extremely popular cross-platform media player and the Android version now has picture-in-picture support. Unlike many other apps, you'll need to use the player's menu to engage PiP while a video is playing. Outside of that quirk, it works really well.
Download VLC for Android (free)
Netflix
Netflix has enabled picture-in-picture support for Android 8.1 only. Tap the home button while a video is playing and PiP just works. There's no word about moving the feature to Android 8.0, but Android 8.1 is said to be released in December for people who don't want to use a developer beta of the operating system.
YouTube Red / YouTube TV
Subscribers to YouTube Red or YouTube TV have support for picture-in-picture as part of the background playing feature. Press the home button while playing a video to enable it, and you might have to allow it in the app's settings. Hopefully, Google will decouple PiP from background playing so everyone has access.
Google Maps
You can press the home button while navigating to enable picture-in-picture, though we would rather everyone keep their eyes on the road!
Telegram
The popular messaging service lets you watch a video someone sent in its own full-screen player, and a tap on the home button will enable picture-in-picture mode.
Pocket Casts
Pocket Casts enabled picture-in-picture support in a recent update and now they support all things Oreo: Adaptive Icons, Notification Channels, and Picture in Picture. Things like this are what makes it one of the best podcast apps you can use on any platform.
Duo
Google's Duo has picture-in-picture support and while in a call a press of the home button shrinks everything down so you can use another app and still be face-to-face.
WhatsApp (beta)
The beta client for WhatsApp offers picture-in-picture support so you can chat with someone else or do anything while on a WhatsApp call. No word on when to expect this in the stable version.
Enroll in the WhatsApp beta program
Chrome (including Dev and Canary versions)
Google Chrome lets you zoom out of any full-screen video that's not on YouTube with a picture-in-picture view. C'mon Google! Do something for most of the world where YouTube Red isn't available, would ya?
When you find a video you want to watch on any feed or Facebook page, tap to play with Facebook's built-in player which supports picture-in-picture when you tap the home button.
A work in progress
This is a living list, and we'll update it as we find more apps that support the Picture in Picture feature. And that's where you can help!
We can't possibly try every app, so please let us know when you find one that's not on our list so we can add it.

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