Runtastic Discrepancies

Options
I've just started using the app runtastic and incorporating it with myfitness pal. It doesn't seem very accurate to me. For example, yesterday it calculated that I walked at an average speed of 2.56 mph for 44 minutes and burned 191 calories. Today it claims I walked at a speed of 3.62 mph for 44 minutes and only burned 189 cal. How is it possible that I walked faster and farther and burned less calories? Anyone else? What am I missing????

Replies