Just wanted to chime in here referring to STL's earlier post. Pings and coordinates of a cell phone can be narrowed down VERY close to a location, often times exact. We've had 911 hang ups that can be narrowed down to a house or 2. Over 4 years ago, my mom had the police knock on her door saying they believe someone called 911 from her yard. I currently have the Lookout app on my phone, and if I was to go online now and log into my account, it will show my phone being in my house. I can even get a street view of the house. My sister's phone was stolen, and we remotely put an app on her phone AFTER it was stolen and was tracking it online as the person was driving around with the phone. Once the phone was stopped at an address, she got the police to meet her at that address to get her phone back.
A little off topic, the lookout app is amazing. It will email you a picture taken using your phone's camera when someone enters my password wrong 3 times. You can also remotely send signals to your phone to engage either the front or rear camera, engage the mic, or even to scream if you can't find your phone because it's on silent. It's actually kind of freaky but I've caught my niece trying to get into my phone on many occasions. It was worth it for me after my phone was stolen while at a restaurant, and I never got it back and lost ALL of my 1000+ pictures.