Quote Originally Posted by Drew Bedo View Post
Well, you could measure the angle of view directly. Mount/clamp/strap the iPad to some support and view a scene . . .a brick wall maybe. Move objects on each side until they are just at the edges. mMasure that angle with a protractor such as is used in school (7th or 8th grade?). Now look up the specs on several lenses and see which focal length most closly matches that field of view.

There is probably a better way to do this direct measurement, but this is what I can come up with just now. I welcome other ideas on how to do this.
Save yourself the time. Check our this site for Field of View of iPhone and iPad devices.

iPad Air is not included in the tests but I have compared it to a regular iPad and the field of view looked to be identical.