Videos Stored in D7-s private file system do not play on Android devices I have .mp4 video files that I store on my D7 site's Private File system. I am using Video JS module for videos.
I am having issues on playing them on devices (Phone, Tablet) running Android OS. 
Does anyone have a solution for this?

I had the same issue on iOS platform, the fix was using Resumable Downloads module for iOS.
For Android the problem still exists.
To make it work on android device you need to pass .webm format along with .mp4 of the same video. Please check sample shown below:

&lt;video id="my_vid_id" class="video-js vjs-default-skin" controls preload="auto" width="640" height="264" poster="poster.png" data-setup='{}'&gt;
   &lt;source src="movie.mp4" type='video/mp4' /&gt;
   &lt;source src="movie.webm" type='video/webm' /&gt;
&lt;/video&gt;