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
RF Link Calc
RFLinkCalc is a numerical calculation tool for radio engineers
$2.99 · In-app purchases
PRICE
$2.99
In-app purchases
BUSINESS MODEL
Paid
No overall Grossing estimate available
RATING
★ 2.3
3 ratings · Below Average
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.
Build your own version
Build Kit
Make this idea yours
A product spec, screen plans, and build steps for your coding agent.
First kit free with a verified email
Add to a Remix
Combine features and design from your favorite apps.
Kit ready. Verify your email to download it.
Generating… usually about a minute.
Make it yours Optional
What should your app do differently? Your note travels with the kit so your coding agent builds around your idea.
What's included14 files
A product spec, phased build plan, differentiation notes, and screen references.
- START_HERE
- AGENTS
- EVIDENCE
- SPEC
- BUILD_PLAN
- DIFFERENTIATION
- skills/
- screens/
Preview a sample Build Kit No email needed
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.
JavaScript is required to complete mailbox verification.
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 RF Link Calc: 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.
Continue in Rork >
Affiliate link: CloneChart may earn a commission at no extra cost
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 more calculators and features for a comprehensive experience.
Assumption to check: Limited functionality compared to competitors
Validate with people who use this workflow before building.
Hypothesis 2
Focus on rigorous testing and quality assurance.
Assumption to check: Low user ratings due to bugs
Validate with people who use this workflow before building.
Hypothesis 3
Implement a modern, user-friendly UI.
Assumption to check: Outdated UI design
Validate with people who use this workflow before building.
Hypothesis 4
Establish better user support channels.
Assumption to check: Poor customer support response
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
RFLinkCalc is a numerical calculation tool for radio engineers. It models the characteristics of an RF link, including Wireless Internet (WiFi) links. You can compute the maximum distance, required transmitter power level, or gain margin. You enter in all of the following values (except what you are trying to calculate) and RFLinkCalc does the rest! Frequency in MHz Transmitter Power in dBm Transmitter Antenna Gain in dBi Transmitter Cable Loss in dB Distance in miles or kilometers Receiver Sensitivity in dBm Receiver Antenna Gain in dBi Receiver Cable Loss in dB Gain Margin in dB The Free Space Loss and Received Signal values are also calculated. The EIRP/ERP Calculator computes the EIRP (Effective Isotropic Radiated Power) and ERP (Effective Radiated Power) in both watts and dBm from the transmitter power and antenna gain. The field strength in dBuV/m is also computed for distances of 3 and 10 meters. The Field Strength Calculator converts between the following units: V/m (volts per meter) dBuV/m (dB relative to one microvolt per meter) dBuA/m (dB relative to one microamo per meter) pT (pico Tesla) dBpT (dB relative to one pico tesla) Tesla Gauss A/m (amperes per meter) mW/cm² (milliwatts per square centimeter) W/m² (watts per square meter)
Written user reviews are not shown here. Check current App Store reviews >
Screenshots
< Scroll to see more >
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
React Native
Expo
Zustand
React Navigation
TypeScript
React Native Paper
BUILD KIT DIFFICULTY
Starter
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.
