My Olympian sister in law just handed over her old Polar M400 GPS watch with a heart rate monitor and everything. It's kinda neat. I already use Strava with my iPhone 6, and have had my doubts towards its accuracy and just assumed my M400 would be far superior in terms of GPS accuracy. When I looked into it, I found this: http://fellrnr.com/wiki/GPS_Accuracy Turns out the M400 is about as bad as it gets. However, I like the HR monitor feature that the watch has added. Any other dork logger users out there how have decided that a dedicated GPS watch was worth the upgrade from a smartphone? What did decide to get?