14.1. The Geolocation API14.1.1. Privacy Considerations14.1.2. Setup Considerations14.2. Getting the Current Position14.2.1. Longitude, Latitude, and More14.2.2. Handling Errors from Requests14.2.3. Accuracy, Timeout, and Cached Location14.3. Putting the User on a Map with Google Maps14.3.1. Showing the Map14.3.2. Centering the Map on the Location of the User14.3.3. Marking the Position of the User14.3.4. Showing Accuracy14.4. Tracking the User's Position14.4.1. Registering for Updates14.4.2. Specific Behavior of the Watcher14.4.3. Watching Position on Google Maps14.5. From Data to Math14.5.1. Distance Between Two Points14.5.2. Sharper Distance Between Two Points14.5.3. The Direction to Take14.6. Building a Compass Web App14.6.1. Create the Mobile Elements14.6.2. The Graduations14.6.3. The Needles14.6.4. The Dial Shine14.6.5. Render the Compass14.6.6. Add Elements to the Document14.6.7. Prepare the Document to Receive Location Data14.6.8. Use Location Data14.6.9. Animate the Compass14.6.10. Prevent Staggering Needles14.7. Summary