VisualRuler is an iOS mobile app which uses advanced computed vision algorthims to turn your iPhone camera into a ruler. Because all cards (credit card, library card, public transport card, ID card...) have unified side lengths they can be used as a reference rectangle to calculate sizes of objects in the plane.

HOW TO USE 1.) Take a picture of an object you want to measure next to any card 2.) VisualRuler will automatically detect the card. If you don't like the detection result you can readjust the reference rectangle. 3.) Add lines or rectangles around objects you want to measure. 4.) Export the result image or share on social networks.