If we compare the two, Facebook is currently a superior place to market a product like Slide. Twitter is more like a general distribution agent. It's like broadcast radio.

I think the hallmark of a really good entrepreneur is that you're not really going to build one specific company. The goal - at least the way I think about entrepreneurship - is you realize one day that you can't really work for anyone else. You have to start your own thing. It almost doesn't matter what that thing is.

I've been developing mobile for years before anybody else really thought it was that important.

Media is very different from financial services. People are very fickle and very vocal. They believe that things should be one way and not the other. It's still very rewarding to build products for huge audiences. It feels like you're making an impact.

The very first company I started failed with a great bang. The second one failed a little bit less, but still failed. The third one, you know, proper failed, but it was kind of okay. I recovered quickly. Number four almost didn't fail. It still didn't really feel great, but it did okay. Number five was PayPal.

As I was getting interviewed by the Wall Street Journal, or some big pub guy, all I remember was that he went off to the bathroom for a second, and they brought out my omelet. The next thing I remember, I woke up, and I was on the side of my own omelet, and there was no one at Buck's. Everyone was gone. They just let me sleep.

Mobile is the perfect example of what is enabling economic growth in the technology sector.