1. Some locations have weak GPS signal or internet connection resulting in location capture inaccuracy. 

  2. Straight line can be due to location inaccuracy, for instance, location tracked inaccurately for few KMs, then return back to normal route.

  3. The pause option is stop the tracking temporarily. If you resume the tracking at the new location, the previous tracked route will be connected to the new route resulting in a straight line as well.