Feature spec
Goal: Send a clear invoice after finishing a job.
- Add a client, line items, a due date, and payment instructions.
- Preview the total before exporting a PDF.
- Keep an editable draft if export fails.
Harmonitron is a harmonic tremolo
$2.99 · In-app purchases
Evidence scope: No current overall US chart position is available. Category-chart positions shown in discovery are a separate scope. Revenue is a directional model estimate, not verified earnings.
A product spec, screen plans, and build steps for your coding agent.
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Combine features and design from your favorite apps.
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What should your app do differently? Your note travels with the kit so your coding agent builds around your idea.
A product spec, phased build plan, differentiation notes, and screen references.
Illustrative example: an invoice app for independent contractors. Your kit is tailored to the app you choose; this is not its generated content.
Goal: Send a clear invoice after finishing a job.
Invoice editor: Client at the top, editable line items in the middle, total and preview action at the bottom.
States: Empty draft, validation errors beside each field, exporting, and a retry action that preserves the draft.
Hypothesis: Contractors need faster repeat invoices more than more templates.
First experiment: Test duplicating a previous job with five contractors. Watch where they hesitate before expanding the feature set.
The full kit adds a phased build plan, evidence notes, tool prompts, and implementation guidance. It is a plan for your coding agent, not a finished app.
Usage: Mechanics are fair game; never reuse the original name, branding, assets, or verbatim copy.
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Good fit for mobile-first iOS and Android prototypes with managed app scaffolding.
Rork plan preview for Harmonitron: map the core Music workflow, choose the smallest differentiated feature set, define the data and monetization boundaries, then prototype the riskiest user journey first.
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These are generated suggestions, not verified review quotations. Check current App Store reviews and speak with users before treating a possible gap as a requirement.
Hypothesis 1
Assumption to check: Limited song selection compared to large streaming services
Validate with people who use this workflow before building.
Hypothesis 2
Assumption to check: Poor user engagement due to lack of social features
Validate with people who use this workflow before building.
Hypothesis 3
Assumption to check: Limited offline access
Validate with people who use this workflow before building.
Hypothesis 4
Assumption to check: No guided tutorials for new users
Validate with people who use this workflow before building.
Original App Store material. Ratings and screenshots describe the existing app, not proof of demand for your version.
Harmonitron is a harmonic tremolo. The rich, swirling amp "vibrato" made famous by early-1960s brownface amplifiers. A normal tremolo just pulses your volume up and down. A harmonic tremolo goes deeper: it splits your sound into a low band and a high band, then sweeps them in OPPOSITE phase. As the lows swell, the highs dip and back again. That contrary motion is what gives Harmonitron its lush, watery, almost phaser-like character that an ordinary tremolo can't reach. Turn the Voice control and the effect morphs smoothly from a classic in-phase tremolo all the way to a full harmonic swirl. Drop it on guitars, keys, synths, pads, drums, or a whole mix. Standalone, or as an Audio Unit (AUv3) effect inside GarageBand, AUM, Logic, and other hosts. THE SOUND • True harmonic tremolo: anti-phase modulation of a low and high band • Voice: morph continuously from classic tremolo to full harmonic swirl • Split & Tilt: place the crossover and balance the two bands • Tube Drive and tone shaping for warmth and grit MOVEMENT • Rate from a slow tide to a fast flutter, shown in BPM • LFO Shape: sine, triangle, square, and ramp with adjustable edge Slope • Tempo Sync that locks to your project and lands on the beat, with musical note divisions from 1/1 to 1/32 (dotted and triplet) • Stereo Spread for auto-pan and rotary-style width HANDS-ON • A living hero orb whose two halves breathe in opposite phase — drag it to set Depth, tap to bypass • Grouped, color-coded controls: Motion, Sync, Harmonic, Stereo, Drive, Output • Factory presets: Brownface, Rotary Swirl, Slow Tide, Sync Chop, Wide Harmonic and more — plus your own saved presets PLUGIN & STANDALONE • Full AUv3 audio-effect support with host presets and parameter automation • Runs on iPhone, iPad, and Mac • Standalone mode with a built-in demo pad, live microphone input, or import a song and export the processed result
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Plan a focused first version with your coding agent. These are planning assumptions, not a delivery guarantee.
Choose one audience and one core workflow. Use the kit to agree on its screens, data, and acceptance criteria before building.
Decide which secondary features, integrations, and platform support can wait. Your version does not need to reproduce everything in the original.
Validate external services, specialist technology, data access, and ongoing costs for your chosen scope.
From the Build Kit assessment.
A reliable timeline needs an agreed scope and a technical check. Ask your agent to estimate the phases in BUILD_PLAN.md after that review.