The Flow of Data: How your data is sold and resold

With all the focus on Facebook over the security of your personal data this week I thought I might share a specific example of how the data you choose to share with apps gets sold and resold.

A while back I installed an app called 'Pizza Compass'. It's actually kind of a cool app. You open it to see a giant pizza slice which is acting as a compass to point you to the closest open pizza place. Kind of gimmicky but it was free all I had to do was share my location with the app. I'm sure most people think "sure I'll let this small pizza app company have my location... why not?". Unfortunately, that is far from the truth. What really happens is the following.

1) The pizza compass app will sell your location data to a data aggregator company. Data aggregator companies buy data from all flavors of apps.

2) The data aggregator company will then sell this data to another company who can use this data to enrich other data and then sell it again.

Sounds confusing I know. Let's walk through a specific example. For example, there are telecom companies with access to data that know what cell phone number belongs to what carrier (240-277-5453 is AT&T etc). These companies then purchase the location data from the data aggregator which associates phone number to GPS location. They now have your location and your carrier. Then can then further enrich this data to check if the GPS location falls inside the polygon of a known competing carrier store (Verizon or Sprint store). Now they know maybe you are considering switching carriers which is a truly valuable piece of data. Now this enriched data set is ready to sell. The telecom company will then go to Verizon or AT&T or Sprint and say "hey would you like to purchase a data set of existing customers who have visited your competitors in the last month?". The answer is definitely yes and that data set comes with a hefty price tag.

So you can see how innocently allowing apps access to your location can provide businesses with extremely valuable insight. You may not realize how many apps you are sharing your location with. In fact up until iOS 11 for iPhone if you had Uber installed your were sharing your location all of the time even if the app was closed (scary right).