In terms of GPS functionality, technology called 'Hot Fix' locks onto satellites faster and locks down on them longer which is good because you're running. Since the Garmin Forerunner 210 is primarily marketed and used as training aid to runners, a listing of the Training Features is necessary. Unlike the Garmin Forerunner 110 that only offered 'Average Lap Pace' the 210 allows for Current Pace, Average Pace over an entire run, and Interval Training (which you can customize with the time and distance of your choosing).
The Heart Rate Monitor is integral to the serious athlete because it really is the only true way to calculate the intensity of your workouts and your conditioning level. Since the 210 is a later Forerunner addition, the improvement to this feature is worthy of noting because it's not as heavy and burdensome now.
With a lighter, elastic strap, the new monitors are much more comfortable to wear. Furthermore, the built-in calorie calculator is really handy although sometimes depressing when you realize just how hard you have to work to burn a significant amount of calories. By the way, if you’d like to see what is available in this category from companies other than Garmin, you should take a look at the top GPS running and fitness watches.
The alerts the Garmin 210 gives you when you leave your customized heart rate target zones are also phenomenal features. Garmin’s Online Connect Portal enables you to track your performance over time, set fitness goals, share your runs with fellow runners, play back your runs like a highlight reel, and even plot your routes on Google Maps.