How do I view my Frequent Locations in iOS 8?
iPhones have been tracking your movement for some time now (if you have Location Services turned on). You can see all the places you have visited recently, including duration of your stay. You can view this in list form or see it on a map. Head to Settings -> Privacy -> Location Services -> System Services -> Frequent Locations. Here you can toggle Frequent Locations on/off and see a list of locations. Click on a location to see it on a map with greater detail, including how many visits you've made and for what duration.