Smart Distance Pro is the extended set of Smart Tools® collection (golf-rangefinder, speed).
This range-finder(telemeter) measures the distance to a target by the camera perspective. The effective distance is 10m-1km. To measure the distance, you should know the height(width) of a target.
Don't worry!! Man's height is 1.7m(5.6ft), a golf flag is 7ft, a bus is 3.2m(10.5ft), a door is 2.1m(7ft). We can guess the height(width) of almost everything. If you know the airplane model, you can measure the height of an airplane. For reference, Boeing 747's width is 72 meters.
Usage is simple. Input the height of an object, and touch your screen. When the target is aligned by 2 green lines, get the value.