The easiest way to report inappropriate and/or stolen photos is to use the "report" button in the app. To do that:
1) First open the photo you want to report and tap it once.
2) Three dots will appear in the top right corner, tap on the three dots, and click on "Report" option.
In order to report a user, simply send us his username and the reason for reporting that user to firstname.lastname@example.org.