This document contains summaries of 10 peer review exercises that discuss GPS, car navigation systems, and how to track cell phones using GPS services. The summaries explain how car navigation systems use GPS satellites to calculate a user's location and provide turn-by-turn directions, and how GPS tracking services like Family Locator and MobileMe allow users to view the real-time location of a cell phone on a map. The summaries are concise explanations of the key points made in each peer review exercise.