It's funny how we all kind of know we're being tracked, but we're more than willing to let it slide in exchange for owning a smartphone. However, you may still get kind of curious about what exactly your phone knows about you. There is a way to figure out just some of what your phone has recorded, so if you'd like to know, you should check it out!
The one people are most interested in is location. To figure out where your phone knows you've been, go to Settings > Privacy > Location Services > System Services > Frequent Locations and you'll get a full list of everywhere you've been with your iPhone. If that's not creepy enough, it will also tell you exactly how long you spent in each location. Not weird at all!