Wait for next update
Perhaps, it is a problem of ios 9.2 beta, or iphone 5, but after the last update there is no way to see videos.
* All my downloads are broken
* The app says, that you should turn device to see a video, but nothing happens
Though, you may see lectures online (there are links to download in courses) via standard video player, and if you do this, you can rotate device to the left, or to the right (in the past only rotate to the right worked).
arz.freezy about
edX: Courses by Harvard & MIT, v2.0.0