A lot of friends in their 30s were getting bloodwork done and realising their testosterone was low. Energy, mood, libido — all below baseline. But outside of Reddit threads and sketchy supplements, there’s no simple, science-backed way to actually track and improve the habits that affect it.

So I built Mojo — a minimal, private iOS app that helps men log the key lifestyle factors that influence testosterone and overall vitality.

Each day, you check in with a few quick sliders: sleep, stress, libido, energy, workouts, diet, alcohol, supplements, etc. It takes under 30 seconds.

From that, Mojo generates a daily vitality score based on your inputs and shows weekly trends across pillars like physical recovery, hormonal balance, and mental state. Over time, it surfaces meaningful correlations (e.g. poor sleep → lower libido → reduced score), helping users understand what’s dragging them down or lifting them up.

You also get concise, referenced tips and articles — designed to cut through the noise and explain how sleep, stress, and training actually affect hormones. No fluff, no bro science.

The app is fully local: • No account creation • No server • No third-party data collection • Optional Apple Health integration (for syncing workouts and sleep)

Mojo is designed to be low-friction but genuinely useful — a tool for building consistency and insight over time.

It’s available now on the App Store for a one-time £4.99.

Would love feedback from the HN crowd — especially anyone into quantified self, mobile UX, or digital health.