Yes, there's an app for that. It's relatively simple, just cut a square hole slightly smaller then the size of your cell phone's screen, find something to hold it against the pumpkin; I used metal skewers and finally find a video animation of some eyes -or mouth or whatever. Make sure you're video app has repeat (hard to find one that doesn't). You may also want to consider power. Make sure you leave enough room to plug in your charger just in case.
A Pumpkin (really?)
A cell (smart) phone (probably one you don't use anymore).
A video playing app that has a repeat feature (ex. "MX Player" for Android)
One or two metal skewers.
Plastic Ziploc baggy (sandwich sized will do).
Your choice of video animation. I've found a few on youtube.com
If you can't download the videos from youtube you can always use http://keepvid.com/ .