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Sungjin Kimleft a comment
Hey Product Hunt! 👋 Sungjin here, founder of MOJO KING and 6Letters. I spent 15 years running clinical trials across pharma — biourology, endocrinology, cardiovascular, CNS — before building this. The question that kept bothering me: why can we track sleep, heart rate, and glucose in real time, but testosterone — which drives energy, mood, libido, and metabolism — still requires a clinic visit...
MOJO KINGYour Apple Watch can now estimate your testosterone. Daily.
Most men check their testosterone once a year — at best. But T levels fluctuate 30–50% throughout the day and are one of the earliest signals of energy, mood, and metabolic health.
MOJO KING estimates your testosterone daily using your Apple Watch's PPG sensor and HRV patterns. No blood draw. No clinic visit. 15 seconds on your wrist.
MOJO KINGYour Apple Watch can now estimate your testosterone. Daily.
Sungjin Kimleft a comment
Great roundup! One biomarker that's conspicuously missing from most Apple Watch app lists — testosterone. We just launched MOJO KING, which uses the Watch's PPG sensor and HRV patterns to estimate testosterone levels daily. Trained on 200K+ ECG records (UK Biobank) + NHANES data. R²=0.887. You mentioned the Watch is "a medical device on your wrist" — that's exactly the gap we're going after....
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