Did you know how many friends in your IM? Some of them you are not familiar with, but your friends close to you are their friends..So your get acquainted with friends‘ friends easily in a complicated social network.
Figure out the relationship for suspect and his/her friends is helpful for investigation. Let‘s take iPhone for example. A very thoughtful function called "Set up family sharing". With Family Sharing, family members get immediate access to each others’ music, movies, TV shows, books, and apps, and can download them to their own devices any time they like. But guess what? It could also let family members know where your iPhone is.
Family members could help you to find your lost or stolen iPhone. Also LE could know where suspect is. All they have to do is to ask for suspect‘s family member‘s help to locate suspect‘s iPhone location. Use [Find My Friends] and suspects "show up" in the map because suspects allow friends to do so.
Now you know thoughtful function makes people get more and more close in the air~
Thoughtful function is also good for investigation
原文：http://www.cnblogs.com/pieces0310/p/6124014.html