I would be surprised if many people would agree with you.
Candy Crush, Dropbox and 4 pics 1 word are three incredibly well thought of applications which have provided entertainment and practicality (in Dropbox's case) to millions of people around the world.
So, saying they are 'some of the worst' applications on the iOS App Store couldn't really be further from the truth. In fact, many would argue these are three of the best applications app consumers have ever seen.