Neither useful nor entertaining

This is a misleading and ultimately useless application. Any "results" obtained are dubious, because they will depend heavily on lighting conditions (which alters how visible the iPhones screen is). While some might claim it still gives you an indication of vision, well, yes, but *anything* can do that. See if people can read the names of the apps on your iPhone. Or a menu. You dont need 20/20 vision to see that this app is worthless. Maybe the medical author should wait until he finishes med school and try again.

SomeActualData about EyeChart - Vision Screening