Prexist

You know how you get an idea and wonder if someone already built it? This lets Claude search nine different platforms at once to find similar existing products. The source doesn't spell out which platforms, but the premise is solid: instead of manually checking Product Hunt, various app stores, and startup directories yourself, you ask Claude to do a comprehensive sweep. Reach for this when you're doing market research on a new product idea or validating whether there's already something out there that solves the problem you're thinking about. Saves you from reinventing wheels and helps you understand the competitive landscape before you start building.