[iMore Question]

I need to crop the videos I have to be closer to landscape orientation.

[TripleOne]

Hello there,
Open the video that you want to crop via the Photos app. At the bottom right there is a slider icon, right next to the rubbish bin. Click on it, and simply adjust the length of the video that you want to crop out. Please see the screenshots I have attached down below.

[SwitchBeach]

The OP seems to be asking to CROP (the image size/scale and orientation) not TRIM (the video length).

OP, you will need a third party app to do that. There are many. I use Videoshop. to edit videos on my iPhone.

[TripleOne]

The OP seems to be asking to CROP (the image size/scale and orientation) not TRIM (the video length).

OP, you will need a third party app to do that. There are many. I use Videoshop. to edit videos on my iPhone.

Whoops!
My mistake.
You can crop videos? That's pretty cool, I didn't know about it until now.