iPhone (1) - different applications

Navigation-Based Application
http://gigaom.com/apple/iphone-dev-sessions-create-a-navigation-based-application/

OpenGL ES Application
http://iphone-3d-programming.labs.oreilly.com/ch01.html

Tab Bar Application
http://www.roseindia.net/tutorial/iphone/examples/iPhone-TabBar-Application-Tutorial-UITabBar.html
http://www.youtube.com/watch?v=Dh_I4juJKrI

View-Based Application
http://www.mobisoftinfotech.com/blog/iphone/iphone-view-based-application-from-scratch/

Utility Application
http://humblecoder.blogspot.com/2009/04/analysis-of-xcodes-utility-application.html

Window-Based Application
http://www.iphonesdkarticles.com/2008/07/first-iphone-application.html