I've been there done that, so I get the frustration you went through. Lesson # 1 What people say is cool doesn't mean that it's something that they'd use. Just because you say you're building the next Facebook will get you some "that's cool" responses but doesn't mean they'd actually use it.
One of the most useful things I do to validate an idea is to actually use YC's application- if you can't answer all the questions about your idea without any doubts, you're don't have a solid idea yet. And validating your idea means to follow up at the very least with the people that said it was "cool". Forget the stealth startups, be completely transparent in what you're building and have beta users follow you from day 1.
One of the most useful things I do to validate an idea is to actually use YC's application- if you can't answer all the questions about your idea without any doubts, you're don't have a solid idea yet. And validating your idea means to follow up at the very least with the people that said it was "cool". Forget the stealth startups, be completely transparent in what you're building and have beta users follow you from day 1.
Good luck with your next thing!