Not safe for kids under 18
Happn is a dating app that tells users if they crossed paths with other users that have the same set preferences (age and gender). Users can upload and browse profile pictures and bio descriptions, including audio clips. If two users like each others’ profiles, they can directly message one another. Sexual/Mature content is likely.

In-depth breakdown

Minimum Age Requirement
Messaging Capabillities
After users cross paths, they can secretly like the other person’s profile and then connect if reciprocated, or directly send a message. If both users approve of the others’ profile/bio, they can send direct messages, along with a single time-limited voice and video calls.
Location Sharing
While specific location is not shared with other users, the app does show places where you cross paths with other users.This setting can be turned off.
Parental Controls
None, though Apple and Android parental controls could be used at the device level.
Happn is premised on connecting users who could bump into each other in real life.