For about a year now, Google has been making slow progress in improving the video viewing experience in its Photos app, and the latest update brings in some cool features. The app will now allow you to pinch-to-zoom videos as well as dobule-tap.

Once you’ve zoomed in on a video, you can trace and watch specific areas of the video for a closer look. A double-tap, on the other hand, will fill your phone screen with the video and a double-tap for a second time will zoom out.
It has been reported that the feature is only available for certain users and the app version is not a factor, which means this is a server side switch. You may have to wait a while before you can start zooming in on your high resolution videos.
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