About the Author

Joseph Hoffman is an electrical engineer who does freelance web and iOS development in his spare time. In 2012 he started NSCookbook.com, which is an iOS programming tutorial site that provides tutorials in recipe format.

Hans-Eric Grönlund has developed software professionally since 1990. He’s currently an employee at Knowit, a leading Scandinavian IT consultancy company, where he helps teams develop software with agile methods.

Software development is not only Hans-Eric’s profession; it’s also his hobby. In his spare time, he has taught himself how to write programs in many different languages on various platforms. His latest passion, obviously, is Objective-C on iOS. Hans-Eric’s Twitter ID is @hansEricG.

Colin Francis is an iOS developer originally from Maryland. After studying iOS development with the assistance of Shawn Grimes, the two of them authored iOS 5 Recipes (Apress). He currently lives in Miami, where he works primarily on music-based applications for iOS.

Shawn Grimes and his wife, Stephanie, run Campfire Apps, LLC, a mobile app development company focused on apps for children and families. Together, they have started the APPlied Club program, which teaches mobile app development to high school students. Shawn is active in the Baltimore, Maryland, development scene and co-runs the Baltimore Mobile Developers group with Chris Stone.