What the user taps. What they see. What they feel.
No tech jargon until the final paragraph.
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You open the app. The phone screen is almost entirely dark — deep crimson fading into black, like the inside of a closed eye. One line appears, letter by letter, as if being typed by something slow and deliberate:
> "your heartbeat told a story tonight."
No logo yet. No buttons. Just that sentence and the sound of a single, slow heartbeat pulse — one beat, then silence.
After two seconds, the full wordmark surfaces: HEARTPRINT, in a tall serif font, white on crimson. Below it: Tuesday · May 13. The date glows faintly, like an ember.
Feeling: awe, mystery, ritual.
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A slow upward scroll reveals the story — cream text on dark crimson, justified, a font that feels borrowed from a novel:
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The day began before the world did. At 4 AM, when the city was still sealed in sleep, you were already awake — not jolted, but arrived, as if you had been waiting just below the surface. Breath work first. The slow expansion. Your heart, still unhurried, memorizing calm before the storm it knew was coming.
By 5 AM, you were training. Your heart climbed fast and stayed there — not frantic, purposeful. This is the hour that defines the rest. The body under load is the body being built.
The middle hours were different. Deep in agent work, the world contracted to a single thread of thought. Your heart settled into a steady, quiet rhythm — the signature of focus, of a mind that has found its task.
Evening came loose and late. The second wind arrived around 10 PM, unbidden — the kind that only comes to people who have learned to tolerate the long middle. Your heart lifted again, not with exertion but with something quieter. Possibility.
Tonight, your body wrote this. You just lived it.
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At the bottom: a single crimson button — ▶ Listen to your future self read this.
Feeling: intimacy, transformation, awe.
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A minimal SVG graph slides in: 12 points on a curved line across the day, labeled in IBM Plex Mono. The peak is a red dot at 5 AM — annotated "Training. HR 158." A secondary soft peak at 10 PM: "Late-night focus. HR 82." The resting valley at 7 AM: "Breath work complete. HR 48."
No axes. No numbers along the side. Just the shape of the day as a body felt it.
Below the graph, in small mono type: "12 moments captured · 24 hours reconstructed."
Feeling: status, quantified-self dopamine, wonder.
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Full-screen. Crimson. A large circular play button in the center — cream border, pulsing softly like a heartbeat.
Below it: "Your future self is ready."
You press play. The audio begins. A voice — unhurried, warm, slightly slower than natural speech — reads the story from Screen 2. The waveform beneath the button moves in sync.
When the story ends, the screen simply says: "Good night."
Feeling: intimacy, transformation, ritual.
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A grid of story thumbnails: the last 30 days. Each card shows only a date and one line from that day's story — the strongest sentence. Cards for May 12, 11, 10... growing smaller and slightly more faded as they go back in time, as if memory is being honored but not clung to.
Tapping any card expands it to the full story. Long-pressing offers: "Listen again."
Feeling: dopamine, memory, ritual continuity.
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Not a wall. A gentle gate.
A cream card appears mid-scroll with a single bordered line:
"Daily story generation · $9 / month — early access, locked forever."
Below it, in small type: "Free read-only access every weekend. No stories generated — just the ones you already have."
One button: Start generating my story. One link below it: "Not yet — remind me Friday."
Feeling: scarcity, respect, low pressure.
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At the bottom of every story: a Share button. Tapping it generates a static image card — crimson background, the one strongest sentence from the story in large Cormorant Garamond serif, date in small mono below it, and the HEARTPRINT wordmark in the lower right corner.
> "Your body wrote this. You just lived it."
> Tuesday · May 13 · HEARTPRINT
Ready to post to Instagram Stories, X, or iMessage. No username. No follower count. Just a sentence that feels true.
Feeling: status, intimacy, viral hook.
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Built as a single-file PWA (HTML + embedded CSS + SVG). Biometric data in v1 is hard-coded from real observed patterns. Audio narration via AWS Polly Ruth voice, generative engine, SSML-paced. Demo video via Veo 3. In v2: Apple HealthKit integration via native iOS app, real-time story generation via Claude API, voice cloning via ElevenLabs.
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