There are far, far too many, and 95% of them are not very good. Even if you wanted to evaluate them all to try them out, this is actually quite hard - my searches start returning a mix of completely unrelated apps and relevant apps after a small number of results.
I know that the specific app isn't your point - it's more about the general question of discoverability, but I rarely find too much difficulty finding at least one reasonable example of the kind of app I'm searchig for.
