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.
App Overview
Marine Compass Pro
Navigate with confidence — and stay safe — with Marine Compass Pro, the
$1.99 · In-app purchases
PRICE
$1.99
In-app purchases
BUSINESS MODEL
Paid
No overall Grossing estimate available
RATING
N/A
No ratings yet
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.
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Build Kit
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A product spec, screen plans, and build steps for your coding agent.
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What should your app do differently? Your note travels with the kit so your coding agent builds around your idea.
What's included15 files
A product spec, phased build plan, differentiation notes, and screen references.
- START_HERE
- AGENTS
- EVIDENCE
- SPEC
- BUILD_PLAN
- DIFFERENTIATION
- skills/
- screens/
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Illustrative example: an invoice app for independent contractors. Your kit is tailored to the app you choose; this is not its generated content.
Screen plan
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.
Differentiate and validate
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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Free quick prompt For a smaller starting point
Quick prompt
Good fit for mobile-first iOS and Android prototypes with managed app scaffolding.
// RORK SYSTEM PROMPT
Rork plan preview for Marine Compass Pro: map the core Navigation workflow, choose the smallest differentiated feature set, define the data and monetization boundaries, then prototype the riskiest user journey first.
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Opportunities
AI-GENERATED OPPORTUNITY HYPOTHESES
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
Add social sharing and location tracking features
Assumption to check: Limited user engagement due to lack of features
Validate with people who use this workflow before building.
Hypothesis 2
Implement offline maps and compass calibration
Assumption to check: Poor offline functionality
Validate with people who use this workflow before building.
Hypothesis 3
Provide tutorial or onboarding for first-time users
Assumption to check: User confusion over compass usage
Validate with people who use this workflow before building.
Hypothesis 4
Allow users to customize compass appearance and settings
Assumption to check: Lack of customization options
Validate with people who use this workflow before building.
App evidence
Original App Store material. Ratings and screenshots describe the existing app, not proof of demand for your version.
App Store description
Navigate with confidence — and stay safe — with Marine Compass Pro, the all-in-one tool for boaters and sailors. Real-time heading, speed and position. One-tap save for any spot you want to remember. A background anchor watch that wakes your phone if you drift. Marine weather. All in your language, wherever you sail. Whether you're crossing the Baltic, dropping anchor in a quiet cove, or learning the ropes on a weekend trip, Marine Compass Pro keeps the essentials front and center. KEY FEATURES PRECISE COMPASS True or magnetic heading, with optional Course-Up rotation so your direction of travel is always at the top of the dial. Smooth, sensor-fused readings you can trust. SAVED POINTS OF INTEREST Name a spot on save — or enable Quick Save and skip the prompt for true one-tap capture. See live distance and bearing from your current position to every saved point. Tap Navigate to make any point the active waypoint and the compass guides you straight to it. ANCHOR WATCH Drop anchor in the app, pick your drift radius (15, 30, 50 or 100 m), and your phone wakes you with a notification if you slip outside it. Keeps monitoring in the background with the screen locked. MAN OVERBOARD (MOB) One tap saves your current position with a red flag and instantly makes it your active waypoint, so the compass guides you back to the mark. MARINE WEATHER Current wind speed and direction in knots, gusts, wave height and period, plus sea-level data for your exact position. SUN AND MOON Sunrise, sunset, solar noon and moon phase for your current location. Handles polar night and midnight sun. TRIP STATS Average and maximum speed for the current session — handy for log entries when you get back to shore. SHARE AND EXPORT Share any saved spot via the system share sheet, or export every point as a GPX file you can import into Navionics, Aqua Map, your chartplotter or any other navigation app. SUNSET REMINDER Optional notification 1 hour and 15 minutes before sunset, so you're never caught out in the dark on the way back. CUSTOMIZE EVERYTHING - Light, Dark or System theme - Heading in degrees or mils - Compass mode: magnetometer (magnetic) or sensor fusion (true north) - Smoothing: Low, Medium or High - COG update interval: 1, 5 or 10 seconds - Independent on/off toggles for each notification type - Show or hide any home-screen readout - Haptic feedback control SPEAKS YOUR LANGUAGE Fully localized in English, Swedish, German, Spanish, French, Italian, Portuguese, Russian, Japanese, Korean, Chinese and Arabic. PRIVATE BY DESIGN Your location is used only to power the compass and the optional anchor watch. We never sell it, never share it with third parties, and there are no ads. No account required. Perfect for boaters, sailors, kayakers, paddleboarders, fishermen, and anyone who wants to know exactly where they are on the water. This app uses Apple's standard Terms of Use (EULA) https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Written user reviews are not shown here. Check current App Store reviews >
Screenshots
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Build scope
Plan a focused first version with your coding agent. These are planning assumptions, not a delivery guarantee.
Define the first version
Choose one audience and one core workflow. Use the kit to agree on its screens, data, and acceptance criteria before building.
Set boundaries
Decide which secondary features, integrations, and platform support can wait. Your version does not need to reproduce everything in the original.
Check the hard parts
Validate external services, specialist technology, data access, and ongoing costs for your chosen scope.
SUGGESTED BUILD STACK
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BUILD KIT DIFFICULTY
Advanced
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.
