Default A.I Watch App Contest

Hi everyone,
I was have an Idea to organize a cool A.I Watch app contest with nice prizes:
All A.I Watch community will be part of the Judge.
Each app will be as well display in A.I app store and will be A.I Watch Certified.
The question how much time you think the contest will need to during so all the developers will be able to present there apps ?
You are welcome with ideas, suggestions etc...

Best Regards
Damien Douk
A.I Watch Creator