You own your data and that data is private. Data (such as listening history) downloaded from Facebook is stored solely on your computer. None is ever sent to my server nor any other server. These local data can be erased by clicking the "Log Out" button at the top of Relisten.
Standard analytic tools are used to track the number of users that visit the site, the countries from which these requests originate, and the operating system and browser used to access Relisten. These data are collected to ensure compatibility with all user's computers and to gauge popularity of this application. No personally identifying information is stored.