When i did my driving test, it involved a simple eye test, and one can practice for that online. It involves looking at an image of what a number plate at a distance will look like.

Point is, this probably is a case of not knowing such tools exist but an app is not needed for this. Also besides telling me my eyesight is weak, what else does it do? Does it tell me what corrective lenses should i get? Guess no. So if i have blurry vision, i think I'll know if i can't read adverts etc from a distance on the street .