Record video in 16:9 aspect ratio on the iPad running iOS 11
Double tap on the screen while the camera is in video mode. That will switch the aspect ratio between 4:3 and 16:9.

I was fooling around with my iPad 2 and I found that you can change the aspect ratio when taking video! (not sure if this works on other iOS devices running iOS 4.3) But all you have to do is go to your iPad 2’s camera app, and double tap on the view finder. (I double tapped on the right side of the screen).
That’s it! Now you can record widescreen (16:9 ratio) 720p video instead of the regular “legacy” full screen (4:3 ratio) 720p video!

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