According to the "Man in Black", a number of select individuals were chosen by Jacob as candidates to replace him in the job of protecting the Island. He further alleges that Jacob is responsible for selecting these individuals and bringing them to the lost Island.

You can be a Candidate, so your friends.

Use this app to check it using the electromagnetic fields analysis.
Discover if you were chosen for a destiny of adventures.
Use the iPhone camera to discover if your friends are candidates too.
Check statistics to see how many candidates are around us.

PS:
Timelines jumps, results may vary, look at purple flashes! :)