Watching video on iPad is a joy but the default Videos app does not play the popular Xvid format videos. There is an app for it now: [CineXPlayer](http://cinexplayer.com) is a Xvid player that plays back Xvid video on the iPad without the need for conversion.
Apple is not known to be friendly to apps that promote other video format. So get this free app while you can from the App Store. Below is an instruction video on how to copy Xvid files from iTunes to the iPad.
[CineXPlayer iTunes Link](http://itunes.apple.com/us/app/id384098375?mt=8)