I'm going to tell you what I did when I was 14 (I had played with HTML from 12 but nothing else) and was just starting out.
I didn't care what I did as long as it was legal and made money from $0. The result was the first 'venture' I did was "forum boosting" - I literally was paid by forums owners to create fake accounts on their forums, and post on them.
Now, I'm not telling you to go and do forum boosting (even though its profitable some 8 years later) what I'm trying to say is, do you want to make money from it right now?
If YES, then who cares if someone else has done it or if its better. Look at Betamax Vs. VHS (amongst a ton of other examples) just build something that makes money and ensure everyone knows about it, who cares if its not as good or even just as good because if everyone knows about yours and not about the other just as good/better service, you win.
If NO, then get involved in some open source project(s) and when something you seem interested in appears, then do that.
If the answer is a mixture of the two, then you still probably should get involved in some open source project(s) so then when something does come along you find interesting then you can just do that.
Who cares if someone else has done it or you don't think you can do it better right now because, you may actually be undervaluing yourself and can actually do it better than those guys.