LensTutorial is a free iOS app that demonstrates in a clever interactive way how your camera and lenses work together to create the precise photo you are looking for. While not designed for the iPhone's camera, where most settings are automatic and there is no optical zoom, there seems to a lot of interest in apps for photographers who want to move beyond the iPhone camera, as good as it is.
The app lets you select your camera by brand and model, and then shows you the effect of aperture, zoom and distance. The on-screen display is designed to emulate the markings on a lens, so it is easy to transfer what you learn in the app to your actual camera. Seasoned photographers know these things, but it is a mystery to many novices so the app re
