Underdog
Underdog
Heart rate zone training with weekly leagues. Apple Watch. Free.
Domain rating
0
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Popularity
Emerging
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About tool
Reads heart rate from Apple Health and scores every minute in zones 1-5 — no manual logging. Weekly Bronze to Diamond leagues, private leagues and zone breakdowns. Free with no ads.
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Great advertising opportunity
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Last modifiedJul 31, 2026
Date listedJul 31, 2026