Jailbreak I guess, or you're crazy rich!
But seriously 900$ is too much IMO but that's a great find, i've never heard of that before.
at least this does somthing. there was an app called I am rich that sold 8 copies for 1000$ each and did absolutly nothing. http://www.betanews.com/article/Apple-pulls-1000-App-Store-gem-after-eight-downloads/1218209274
i think it has no instructions so that professionals who know alot about how wireless survielence works can use it.
like they are experienced and dont need instrusctions to read