Millimeter is the best free screen ruler app. Full screen is available for measurements. There are no ads in the app. Manual calibration is available, so any device can be calibrated for accurate measurements.
Measure small objects on the screen with this ruler app.
You can purchase extra features or modes in the app if you need it.
Units: millimeter (mm), inch (in). Fractions are supported for inch units.
- German, Russian, Japanese and French languages.
More about app: http://goo.gl/304nJB