This is one of the very first objections we hear when working with a new client and talking them through the Apptrepreneur brand Startup Program process. "But if I'm talking about my idea to everyone I can and showing it long before I'm certain what to build, isn't someone going to steal it from me? Do I need non-competes, non-disclosures and the mob to enforce a cone of silence?"
It IS entirely possible that someone could decide you have a great idea and try to build it and launch it before you. The truth: We've never seen it happen.
Remember that competition isn't a bad word; in fact, competition in your space proves to investors that there is an ample market (which translates into good ROI) for what you're doing. And the likelihood of someone stealing your idea, getting it out before you, AND it being a better implementation... Well that's like winning the lottery. Twice. In the same week. Read: Probably never going to happen.
Like we've said before, execution is key. So go execute your pants off and stop worrying about the unlikelinesses of life. (What, that's a word!)