A long press on the distance icon 
(inside the zoom/scale window) will draw on the map a ruler giving precise distance and direction between 2 points on the map.
You could drag the start or the end point or the ruler itself and see (in real time) the distance and bearing between the start and the end (the point that you drag becomes automatically the end of the ruler).
NOTE: when you drag, the selected point has an offset from your finger, so to be able to see where exactly are you aiming.
