This application does not save any personal data that could lead to identifying its users.
We don't save facebook ids, e-mails, names, locations nor any other personal details.
Even though we use Facebook API to read personal data of a person, this data is not stored in our database and we, as admins, are unable to access it through our app. This personal data is read only during the particular use instance and used to calculate "personal price" for purposes of our art project.
The only details stored in our database upon each use are: timestamp, user's price estimate (the value sent from the landing page form) and the resulting price (a number with no unique identifier).
As should be clear from our code, we have no way how to pair the price/estimate/timestamp with a particular user.