Viewfinder Preview is a must-have app for any stills photographer or filmmaker who wants to verify framing before setting up their big camera. It is an iPhone app that lets you preview camera framing for any combination of camera and lens. You just need to select your desired film or sensor size and focal length, point your iPhone camera at what you want to photograph, and verify the framing. If you are happy with the framing, then you can get the big camera out.

The app includes a large database of camera sensors and film formats, but you can also add your own custom format. The menus are customizable, so you can include the film or sensor formats and focal lengths you care about. The app also comes with a fully configurable light meter, and you can take photos with it, so you have a record of shots you were framing. The app also includes additional data that describes the film format, focal length, and lighting meter settings at the time the shot was taken. You can add notes to your photos, create albums of photos from the same project or trip, and even create PDF documents of albums. The app also supports film stock emulation and wide-angle lens adapter. Viewfinder Preview is excellent for photo sketching, location scouting, or storyboarding, and it's available for iPhone users.