Or an iPhone camera. Using the camera app to record the video. I think I used to be able to speed it up, but now I can’t seem to figure out how.
Are you thinking of the Time Lapse option (swipe over all the way left on the menu at the bottom where you select Photo/Video/etc)?
Or are you asking to make a video that already exists go at a faster speed? For that I think you can open the video in the Movies app and edit the speed from there.
That is the intent. I will see if I can make that work.