i built a heart rate zone training app for runners. ios + apple watch. custom zones, real-time haptics, post-run graphs. all the “smart” stuff you’d expect.

but i never talked to a single runner before building it. not even myself lol. started as a thesis → kept building → added features → added a paywall (€4/month!) → launched it → and yeah… no one cared.

zero feedback. zero users. just code in the void.

i recently made the whole thing free. not trying to “sell” anything now — just seeing if it’s actually useful, and listening this time. curious how others handle this. ever build something 100% wrong?

Comments (3)

_pktm_ · 18h ago

Thank you for sharing the app but even more so, the story. It feels very representative of how a lot of apps start with great goals or intentions.

OccamsMirror · 15h ago

What's a heart rate zone training app?

dotcoma · 16h ago

What does this app do? Why should runners care?

I'm curious; I think you should explain it in a simple line.

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Show HN: I spent 2 years building an iOS app no one asked for

Comments (3)