*** Featured on http://gizmodo.com/5562674/***
*** If you are interested in this tool, you may also be interested in Photographer's Field Tools. It has a distance ruler using map and many other cool features.
Both a screen ruler and camera rulers. Support both metrics and US unit. It can find out an object distance, height and the object size using the phone camera. Just turn on the camera ruler, stand up, aim and get the result instantly.
Supports both phones and tablets.
1. Internet access is for crash report
2. Orientation: It always works in landscape orientation in all camera rulers because there is a bug on android early versions that the camera preview doesn't work in portrait orientation
v3.2 changed the user interface of camera rulers
v3.1 fixed a minor bug when showing the help. only on android versions 2.x.
v3.0 deployed a new way to auto-calibrate the ruler. fixed the camera issue on galaxy nexus phone
v2.1 fixed freeze issue on many newer phones
v2.0 support tablet resolution