I have noticed many times that I will be on a walk or run with Pokemon Go open to try to hatch some eggs and the distance won't seem to update immediately. I'll be at say 2.5km on an egg, run half a mile, and then check it and it will still say 2.5km, then I walk for a minute or so and check and it will be at 3.2km. Yesterday I actually witnessed it jump over .7km in a matter of seconds.
So it appears to me there is a delay with pushing your "distance walked" to the server, presumably to save data/battery over the real-time update alternative. However, I would like to know how long this delay is so I'm not checking my distance every 5 seconds waiting for it. Does this delay change based on your connection? Power saver mode? GPS Precision?
Best Answer
Anytime the "loading" symbol appears in the corner, your distance is usually not being counted. If you wait for the game to finish loading before you walk, your distance will almost always count. The update is dependent on whether it is able to get a good GPS signal but even if you have excellent signal, if the game is loading it will not update until it has finished loading. At least, according to a number of experiments done by a few people that seem to show that distance is not counted while the game is loading. This would explain the jumps you experience as well, I would think. Hope this helps.