Launch an app upon certain external trigger
U.S. Patent No. 8,254,902, otherwise known as "Apparatus and methods for enforcement of policies upon a wireless device," was granted in late-August, and would allow phone policies to be set to "chang[e] one or more functional or operational aspects of a wireless device [...] upon the occurrence of a certain event."

Apple was awarded this patent over the summer. They are looking at ways to disable features like the camera when in range of a certain AP, for example a AP near a locker room or bathroom or at concert and so on.....

Hopefully third party apps can find a way to take advantage of this as well.

Apple Location Software

Link above explains it in much more detail.