Dale Dougherty, founder and general manager of Maker Media, publishers of MAKE Magazine and a division of O'Reilly Media, interviews Alasdair Allan, astrophysicist and author of Learning iPhone Programming: From Xcode to App Store, Programming iPhone Sensors, Basic Sensors in iOS: Programming the Accelerometer, Gyroscope, and More, Geolocation in iOS: Mobile Positioning and Mapping on iPhone and iPad, and iOS Sensor Apps with Arduino: Wiring the iPhone and iPad into the Internet of Things. The interview concentrates on the last of these books and the quickly evolving context within which it was written.