<blockquote>Location Histories for Location Aware Devices</blockquote>
via <a href="http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&amp;Sect2=HITOFF&amp;d=PG01&amp;p=1&amp;u=%2Fnetahtml%2FPTO%2Fsrchnum.html&amp;r=1&amp;f=G&amp;l=50&amp;s1=%2220110051665%22.PGNR.&amp;OS=DN/20110051665&amp;RS=DN/20110051665">United States Patent Application: 0110051665</a>.

LOL.  Apple even submitted a patent for tracking their users.

Update: Here's the relevant method from the patent application...
<blockquote>10. The method of claim 9, further comprising: querying the database for at least a portion of the location history data; retrieving network information from the database that is responsive to the query; translating the network information into position coordinates; displaying a map view; and displaying markers on the map view as a timeline according to the position coordinates, the markers indicating the location history of the location aware device for the time span.</blockquote>