We know Facebook collects lots of data but not most of us know what they collect about us and sell to other organisations.
Data Selfie aims to give you a glimpse by letting you analyze your own Facebook usage, they do not upload your analysis to the server. But after viewing it, you can either export your data or delete it from the dashboard.
While there’s no way to know exactly how Facebook analyzes your data without working in the organisation, Data Selfie gives you a rough approximation, after downloading it from the Chrome store. It thereafter tracks your page visits, how long you stay on a particular posts, your likes and comments.