As a developer it is tempting to avoid reading reviews for apps that have been out for a long time and, one hopes, been polished over many updates. There is no way of responding to reviews on the App Store so for example if someone gives Chirp! a one star review because there is no sound, all we can do is shout at the computer "you've got the mute button on" which isn't helpful. (On that subject, Apple have a reasonably robust review process that all apps and updates have to go through so, really, they are not going to pass a bird song app that doesn't have sound).
Volume issues aside, obviously some people leave poor reviews because they genuinely don't like the app, but sadly one of the other main reasons for unusually poor reviews is that some competitors try and boost their app by leaving inaccurate or misleading reviews for better apps. Shame on them.
I don't want to give the impression that we are complacent. It's just that we have responded and will continue to respond to customers who make suggestions or tell us what they don't like - please continue! But to be sure that you are heard, the best way to contact us is through email, Facebook or Twitter (links above). Looking forward to hearing from you!