My first app was released in July or August of 2008. It was a 'fingermill' - a treadmill for your fingers. My level of programming was quite basic to begin with, so it was more gimmicky to start with. Day one it was up there, I had 79 pounds worth of revenue.

I thought of the idea of Summly in March or April 2011. I was 15 years old and I was revising for some kind of history exam. The problem was I was trying to find information that was useful to me. When you type into Google an esoteric term, you get quite a lot of stuff that's not relevant.

Be fearless and don't be afraid of failure. There is no better way to learn than through trial-and-error.

I was using Twitter a lot on my phone, and was realising there was a massive gap between the link on the tweet and the full story. If you could come up with a summary layer to show in Twitter, that would be awesome.

I don't feel like a different person. My motivation has always been to do technology apps and companies, not making money. Just because the money's come, nothing's changed.

I put together an iPhone app called TrimIt and released that in July 2011. About a month later, the private fund of the Hong Kong billionaire Li-Kashing cold emailed me and expressed an interest to invest, but they didn't realize I was 15. They thought it was a U.K. company with a team.

One thing I'd like to do is angel investing in small companies. That's what's exciting, and if you are lucky to have a bit of money, you can take those risks.