Deal hunters should also check out our Best Amazon Prime Day Deals roundup and Prime Day liveblog. The Best Fitness TrackerFitbit has faced pretty stiff competition over the years (most notably from the Apple Watch), but its flagship Charge line is still the best overall fitness tracker for the money. The Best If You Have an iPhoneThe Apple Watch Series 10 is the best fitness tracker for iPhone users. It still doesn't have blood oxygen sensing due to a patent dispute, but it's otherwise a solid fitness tracker. It's no slouch as a health and fitness tracker, with electrocardiogram readings, sleep tracking, heart rate readings, blood-oxygen measurements, and stress tracking.