Vid.ly is a site that will take a video and convert it so it can be viewed on any device. You It gives you a unique Vid.ly URL and embed code for the video that you can share via email, web site, social network or you can embed the video on a site or mobile app. The video conversions are stored on their site and when someone clicks on the video/link, it detects their device and operating system and then delivers the correct video to them.
It's easy to use - create a URL (name it something that matches your video), enter the URL for the video you want to convert, and off you go.
The free version lets you create and share one Vid.ly URL at a time, but you can create as many URLs as you like, for free.
This is a great resource for education, allowing students and teachers to use any device or operating system to view videos. With so many different systems out there, sharing a video with your students or colleagues is much easier using this system.