I need to write a short description of a new product. The product is a smartwatch designed for fitness enthusiasts. It has features like heart rate monitoring, GPS tracking, and waterproof design. The target audience is young adults who are health-conscious and tech-savvy. Your response should contain at least 3 sentences and use the keywords "fitness", "smartwatch", "health-conscious", and "tech-savvy". Highlight the key features using markdown, i.e., *highlighted section*.
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