How can I slow down the speed a video is played back on an iPhone? I'm viewing courses on coursera (a free classroom site) and the material is just going too quickly.  I need a video player that can slow down the speed of the video just a little bit so I can follow along.

It seems that most video players highlight the ability to stream video, etc, but nothing seems to slow down the speed it plays.

Is there any applet that allows me to play an MP4 (or similar offline file) at a slower rate?
If you don't mind going through an extra step, almost any video editor lets you edit video speed. You could import the video, edit the speed, and export.

If you're looking for a solution that's a bit less time consuming, you could try SpeedUpTV. Although the app isn't free, it lets you adjust playback speed on-the-fly in the app: