Videos by iPhone you can modify them at any time, although the adjustment tool included offer some features, but it does not include the feature cropped part of the video. So, if you want to enlarge a certain part of your video clip and cut the rest, you will need a different tool.
There are some applications that you can use to cut videos on iPhone, perhaps the most notable application iMovie Apple, which can do the job to the fullest.
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How to crop part of a video on iPhone using the application iMovie
Before we move on to the steps of the story, note that the cropping feature is not present in the app technically, as you will have to use the zoom feature. Although an alternative solution but it works.
1) Open iMovie, and click on “Projects” at the top, then click the plus sign.
2) Click on Choose Movie and select your video and click Create Movie.
3) Click on the Stories section at the bottom of the screen. When he shows up button Pinch to zoom video button in the upper right, click on it.
4) Change the dimensions of the selection box and move it to where you want it.
5) when finished, click Done. You can then preview your video or save it or view it or edit it again.