Angle of view

Hi,

We are developing a new version of simulator of eye diseases (the first version available in apple App Store “See My World app”) and we need to know angle of view of iPhone and iPad cameras. It is necessary in order a real sizes of visual defects of people on different sizes of displays (bigg defect on display with 15 degrees camera and smaller on display with 40 degrees camera) will be commensurate. Where we can get an information about angles of view all iPhones and iPads cameras?