After Credits is a free app that you can utilize to easily find out if a movie has any special scenes during or after the credits (aka Stinger, Tag, Kicker, Coda, etc.).
Simply enter the name of the movie you're seeing, click search, and in an instant you'll know if you need to stick around through the credit reel or not.
You can also click on the movie to see media content as well as interactive polls on if it's worth sticking around for the bonus scenes and seeing the movie in 3D, IMAX or HFR.
-- The official app of AfterCredits.com