Here's why...
Tinder is more than a dating app.
People are increasingly lonely and humans crave companionship. If Tinder can reduce loneliness, and enable IRL adventures, it *could* challenge Facebook.
1. 25% of Americans have no confidants or close friends.
2. Only 25% of Americans 60 or older have discussed anything important with somebody under 36 in the past six months.
en.wikipedia.org/wiki/Bowling_A…
Right now, meeting people online is weird. In a decade, it'll be totally normal. If Tinder can capitalize on this emergent social trend, it'll be a massive business.