Hoya eDitest app for iPhone and iPad

eDitest is a free app that allows:
- estimate diameter of the lens
- measure pantoscopic angle
- transpose spherocylindrical lens record
- calculate required lens power according to vertex distance
- calculate contact lens power when optical lens power was given
- calculated optical lens power when contact lens power was given
- calculate prismatic tolerance of mounted & uncut lenses
- determine additional lens decentration associated with the use of prismatic correction
- perform solving and resolving on prisms
- calculate the spherometric power of lens curvature for different index materials
- calculate spectacle magnification