is probably the safest choice, if only because it has a teens-only section that seems to be moderated reasonably well.
For starters, although many of the apps aren't intended for them, it's easy for savvy teens to get around registration-related age restrictions. Location-sharing increases the potential for a real-life meeting; less dangerous but still troubling is the heavy emphasis on looks as a basis for judgment.
It's possible that teens are only testing boundaries with these apps.
Keep lines of communication open; talk to them about how they approach dating and relationships and how to create a healthy, fulfilling one -- and note that they usually don't start with a swipe.1. This flirting app allows users to sign up as a teen or an adult.
They'll get notifications when other users near their geographic area join, and they can search other areas by cashing in points.
They receive notifications when someone "checks" them out but must pay points to see who it is.