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 fucction 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.
You guys could take a look at my blog to see what's going on.
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