FYI, Google tracks you even on airplane mode. So the second you jump back on Wifi your location history is updated. With dead reckoning calculations using your accelerometer and other sensors they know EXACTLY where you've been.

Not sure if they do this on iPhone or just android, but my guess is they do both if you've installed google maps/gmail etc.

https://www.youtube.com/watch?v=S0G6mUyIgyg