iOS has a built in feature that, as far as I can tell, is working like GPS locator. I have been testing this and so far all the dates, times and map locations that my iPhone is collecting are accurate. This feature is on by default and all you need is access into the device to harvest it – no forensic tools necessary.
This all started when I was playing around with iOS 8.1.1 I cam across a “Frequent Locations” feature buried deep within the Privacy options. If you have an iPhone go to this location and see for yourself.
Settings | Privacy | Location Services | Frequent Locations
The locations were all places I had been. For instance, one location showed I had visited it 70 times and listed all seventy dates ranging from 12/4/2014 through 1/21/2015.
The above location is another example showing where I went out to dinner. The dates and time are correct for each row – my iPhone was there.
At this time it appears users must manually choose to “Clear” their history. Further, my dates and times went back an entire year. This all translates into a valuable source of historical evidence.
I plan on monitoring this further to learn more specifics about how this feature behaves. I recommend you do the same.