In his master’s thesis, Frederik Efferenn investigated the use of the dating app Grindr in the urban space of Berlin. Through its GPS-based technology, the app produces a dynamic and homosexual network that gay men use to arrange casual hook-ups. In his work, the author focuses on the diverse media routines that Grindr users practise in the course of an urban sexuality. How does the search for non-committal sex inscribe itself in everyday routines that homosexual men use to shape their lives in Berlin? For the Digital Society Blog, the author presents various central theses from his research in a two-part blog series. Part 1 of the series first introduces readers to the world of gay online sex dating and then contextualises it with four findings from the local use of the app in Berlin.