ScreenCred is an iOS app that helps you see who worked together on your favorite movies and shows. Basically, search 2 movies or shows and it'll show all the common cast and crew between the 2. Works with people too.
You can read all about the development.
As far as I'm concerned, it's pretty feature complete. So I haven't touched it nearly a year. It has dozens of downloads. Why don't you give it a try?