Re-learning a lot today; the iPhoneOS 1.0 SDK is *very* different from iPhoneOS 2.0 and everything after it. Simple things like UIColor, UIScreen don't exist. Even UITableView was 'just’ UITable. UILabel was UITextLabel. QuartzCore was 'LayerKit’. There is no UIApplicationDelegate either, you subclassed UIApplication instead.

Really shows the longevity of a public API contract; almost everything in iPhoneOS 2.0 is very familiar to modern UIKit development