Can I edit a video on my iPhone (the techno-peasant asked hopefully)?

Hi, I took a video on my iPhone that went a bit long. I’d like to cut off the last little bit because it’s not relevant.

Is there an easy way to do that?

Yes, iMovie is free for the iPhone.

Is that an App I can get from the App Store? Then what do I do?

Then, you “share” the video to iMovie, and edit it there.

If you only want to trim the movie, you can actually do that from the Photos app. When you play the movie, there is an “edit” button in the URH corner. Click on that, and the timeline will appear at the bottom. You can select the duration by dragging the sides.