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.
FRETSMITH — THE LUTHIER'S BENCH REFERENCE
$9.99
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.
First kit free with a verified email
Combine features and design from your favorite apps.
Your first Build Kit is free with a verified email.
Generating… usually about a minute.
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.
JavaScript is required to complete mailbox verification.
Good fit for mobile-first iOS and Android prototypes with managed app scaffolding.
Rork plan preview for Fretsmith: map the core Reference workflow, choose the smallest differentiated feature set, define the data and monetization boundaries, then prototype the riskiest user journey first.
Preview ready. Verify your email to reveal and copy the full prompt.
JavaScript is required to complete mailbox verification. Return to this prompt preview.
Affiliate link: CloneChart may earn a commission at no extra cost
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 variety of chords may not satisfy advanced players
Validate with people who use this workflow before building.
Hypothesis 2
Assumption to check: No interactive features for learning
Validate with people who use this workflow before building.
Hypothesis 3
Assumption to check: Static content may become stale
Validate with people who use this workflow before building.
Hypothesis 4
Assumption to check: Lack of user engagement options
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.
FRETSMITH — THE LUTHIER'S BENCH REFERENCE Built by a working luthier who got tired of guessing. 623 guitar and bass models across 47 brands. Every spec verified against manufacturer documentation, model by model. Where a maker doesn't publish a number, Fretsmith says so instead of making one up. One-time purchase — less than a set of strings. No subscription, no account, no ads. It works offline, in a shop with concrete walls and no signal. WHAT'S INSIDE • Brand Specs — 47 brands, 623 models. Scale lengths, nut widths, fretboard radii, truss-rod tools and access points, saddle-slot dimensions, nut materials, and the model-specific traps that cost you an afternoon. Vintage models included. • Setup Checklists — 12 job-aware checklists in working order: electric, acoustic, bass and classical, plus fret levels, refrets, nut jobs, Floyd Rose and neck resets. • String Tension Calculator — exact plain-steel math and published unit-weight data for wound strings, including phosphor bronze. Any gauge, any tuning, any scale. Balance a set and size total neck pull before you buy the strings. • Nut Slot & Intonation Calculators — file-target slot depth, and the exact saddle-compensation direction and distance. • Measured-Spec Comparison — enter your measured relief, action and nut-slot depths. Each is flagged against the model's published spec and the typical working range, so you know what's off before you pick up a tool. • Acoustic Diagnosis — identifies a neck reset before you file the saddle away chasing it. • Diagnostics — tuning-stability and buzz decision trees, plus a truss-rod quick lookup with direction and tool by brand. • Reference — magnet types and pickup heights, 32 tonewoods with tone tags and CITES status, nut and saddle materials, and an action/relief/nut table across 16 instrument types. • Chromatic Tuner — a native pitch-detection engine with an A=440 reference tone. No clip-on, no second app. • Printable Spec Sheets — hand the customer a professional record of the work and the measurements. FOR PROFESSIONALS Fretsmith is a reference tool for trained luthiers and technicians. The procedures it documents can permanently damage an instrument if performed incorrectly. Always verify on the actual instrument; when in doubt, consult a qualified professional.
Written user reviews are not shown here. Check current App Store reviews >
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.
Not assessed in a Build Kit yet.
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.