iOS 7.0.2 works perfectly fine on my iPhone 4S, but one thing I despise is the white backgrounds with tiny light grey fonts they use on most things like the calendar, notes, and email messages. This is a big step backwards for me. The only option you have is to change the font size or make it bold, which helps a bit. I notice Apple does the same thing on its web site. Someone at that company should get an education in the proper use of typography.