Apps such as this does make one despair. What is the point of an app that merely converts between temperatures? I have an excellent universal conversion app. It is easy to use, comprehensive, customisable - in fact it is the perfect conversion app, and it is free. The developer of the iTempConverter says that as he add more "presets" he will make it a paid app. So! who cares when there are much better free apps.
Of course the issue is that with so much rubbish how do you find these gems. I subscribe to a number of blogs and glean them for the best of that which interests me but what of your average punter. With so many useless crudapps, so many duplicates such as individual apps for sports teams or single relative speed-dials, and single use apps such as this temp converter the App Store is maybe 95% useless, maybe even higher.
I can see where Apple has gone wrong. They wanted to tie down the application development for the device to reduce instability and to control its use for a number of reasons. The problem is that it is so easy for your average hack programmer to develop some single function app that every man and his dog can get some piece of rubbish into the App Store. Great model but so open to abuse.
I am hoping that these people get so discouraged when no one is interested in yet another narrow single use, useless app that they give up and go back to kiddie scripting viruses. From the evidence I doubt that this will happen.