FakeCalls is a very simple app. Basically, it just mimicks the phone call receiving process on an iPhone. You load up the app and it will open a page that looks just like the standard iPhone "locked" view. (You can set it to have any background you'd like.) After a set amount of time, your phone will start ringing and vibrating indicating an incoming call.
Of course, there is no one on the other end of the line.
You can set the amount of time the app will wait before it makes the "call" in the settings. It ranges all the way from 0 seconds up to 10 minutes. It'd be nice to see this setting go a bit higher, so you could use it to end a 30 minute or hour-long meeting.
You can also set the name (or number) of the caller to anyone you want in the settings, as well as what number they are calling from (mobile, home, work, etc).
The app, created by developer Sebastian Trujillo is available in Apple's App Store for $0.99. Sure, it's not free, but the amount of time such an app could free up should well be work a buck. Trujillo's company MagicTap.net also promises to give 10 percent of all earnings to charity.