There are 7.9 billion mobile-connected phones on the earth right now, and you probably have at least one of them.

Your phone is constantly tracking and storing your data.

And every day it gathers and produces more and more of that data.

But what does that data say about you?

Can it reveal anything about your relationships with the people you care about?

I found four groups of people who agreed to share a month's worth of location and message data from their phones with me so that I could have answers.