In the very beginning, Yelp started as a service where we really didn't think people would write reviews for fun. The whole concept of user-generated content was pretty nascent in 2004.

If somebody writes a review of a dry cleaner, that piece of content is not wildly viral. It's not like a viral video that can spread across the world in a matter of minutes, so as a result, each market is almost an island unto itself.

Everyone is panicked about the transition to mobile. I don't lose any sleep whatsoever.

Yelp is in a very nice spot: local data, and especially review data, is one of the killer apps on mobile phones.

You have to be very nimble and very open minded. Your success is going to be very dependent on how your adapt.

Starting a company, your success is going to be very dependent on how you adapt. You're going to make decisions, you're going to make bets; most of them are going to turn out to be wrong.

There is this cat and mouse game that plays out over time where our team comes up with new and interesting ideas to identify content that we shouldn't recommend, and over time people are constantly probing that, trying to figure out how can they get around that and get a better reputation on Yelp.