Ruler app designed for objects and maps measurement with various scales selectable. Both units system available: metric (meters) and imperial (Inches, feet and statue miles).
It's possible to measure scaled models to check the corresponding dimensions against the original.
Precise distance measurement by dragging green marker and angles measurement by protractor.
Added possibility to define own scales.
Now (version >=1.4) it's also possible to measure distance on map in scale.
NEW in 1.6:
Added protractor for angles measurement.
Ruler app contains mainly scales for model trains:
*0 (both 1:45 - US and 1:48 - Europe)
*00 - British scale 1:76.2
*H0 - 1:87
*TT - 1:120
*N - 1:160
*Z - 1:220
There are also ruler scales used in other scale models (planes, ships kits etc.):
1:500 000 (ICAO - aviation)