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iOS product
Added August 14, 2026
Underdog — Turn heart rate zone minutes into weekly league points
Visit Underdog↗U
iOS product
Added August 14, 2026
About the product
Underdog is an iPhone app that turns time spent in heart rate zones into a weekly competition. It reads heart rate and workout data from Apple Health, recorded by an Apple Watch, chest strap, or other connected sensor, so nothing is logged by hand. Every minute in zones Z1 to Z5 earns points, and higher zones score more. Scoring uses heart rate as a percentage of a personal maximum, so different ages and fitness levels can score the same. Points feed weekly leagues from Bronze to Diamond, with promotion, relegation, and a weekly reset. Private leagues use an invite code. Free on the App Store, with no ads.
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