I think one of the question to ask yourself is: is that competing product the one I'd have built? Is it a product that would solve the problem I wanted to solve

I think one of the question to ask yourself is: is that competing product the one I'd have built? Is it a product that would solve the problem I wanted to solve perfectly? Is that product awesome? If the answer's yes, you probably should stop. Because at best, you'd make the same product. If not, see where the product fails and try and estimate what could be better and is it worth it. Last, remember that the later you are on the market, the more expensive it gets to get attention. You'll either need cash or need to seek funding.