Precision Ruler is an inexpensive software for smartphone users Apple, the main purpose of which is to integrate meter functions into the phone. The app, priced at less than a dollar, is a sort of advanced ruler interface that you can use to measure objects and leave notes. This small application works in two main modes – fixed and movable. In fixed mode, the user will be able to measure objects at least 9 cm long, while in move mode, the measuring scale is not limited by the length of your smartphone screen. 
There is also a mode with the ability to focus, increase (zoom) objects and turn the device into a measuring device for small objects with an accuracy of 0.001 cm. All objects that the camera can capture can also be measured using the Precision Ruler application. 
In addition to several modes, the user can choose from international units of measurement, including centimeters and inches. In the new version, some bugs have been fixed and the 'sight' in zoom mode has been improved. Developer: Zealotsoft, Inc. Current version: 1.2 Compatibility: iPhone, iPod touch and iPad. Requires at least iOS 3.0. Install from AppStore
