The iPhone app Stilly costs $2 and makes seizure gifs:

https://itunes.apple.com/us/app/stilly-one-button-gif-camera/id648976952

Tumblr staff seems to love it:

http://staff.tumblr.com/post/51808001782/this-is-addictive-check-out-stilly-a-one

Tumblr tag is #stilly ...

http://www.tumblr.com/tagged/stilly

"Stillies, though, can be sent via iMessage, SMS or Tumblr for now, with more sharing options in the works along with a few other features. However, the core experience will remain very basic. And now that the app is launched and people seem to be enjoying it, Ian Broyles says he will work on building an Android version, too."

Other gif making app is gifboom - http://gifboom.com/

Gifboom 

"Gifboom is one of the most popular GIF maker apps and houses a ton of great features. You can actually snap photos through the app or import ones already on your phone, use the front or back facing camera and apply filters similar to Instagram. Once your animated photo is ready, you can easily share it on social media. Gifboom is available both for iPhone and Android."

10 free gif maker apps for iPhone and Android:

http://webtrends.about.com/od/prof4/tp/Free-Gif-Maker-Apps-Iphone-Android.htm

GIF SHOP: http://gifshop.tv/

Coub now sees a million visits a day for its music video gifs:

http://techcrunch.com/2013/06/01/coub/