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
Interval Haptic Coach
Interval Haptic Coach is an Apple Watch interval timer for HIIT, Tabata, EMOM, and simple work-rest training blocks.
$4.99
PRICE
$4.99
No 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.
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 included15 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 Interval Haptic Coach: map the core Health & Fitness 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
App evidence
Original App Store material. Ratings and screenshots describe the existing app, not proof of demand for your version.
Screenshots
< Scroll to see more >
App Store description
Interval Haptic Coach is an Apple Watch interval timer for HIIT, Tabata, EMOM, and simple work-rest training blocks. Use it to: - start interval workouts fast from iPhone or Apple Watch - feel each work-rest switch with wrist haptics - run Tabata, EMOM, and custom interval plans - preview the same plan on iPhone before training - pause, skip, or restart when the workout changes - stay fully offline with no account, ads, or subscription Why people buy Interval Haptic Coach: - faster and cleaner than ad-heavy workout timer apps - watch-first haptics keep your eyes up during hard reps - one paid download instead of recurring timer fees - local-only design with no cloud processing or tracking SDK Interval Haptic Coach works best for: - HIIT and circuit training - Tabata and EMOM sessions - running, treadmill, and conditioning blocks - anyone who wants a simple Apple Watch workout timer
Written user reviews are not shown here. Check current App Store reviews >
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
Provide more flexible interval settings and templates.
Assumption to check: Limited workout customization options
Validate with people who use this workflow before building.
Hypothesis 2
Integrate social challenges and sharing options.
Assumption to check: Lack of social features
Validate with people who use this workflow before building.
Hypothesis 3
Offer detailed analytics on workouts and progress over time.
Assumption to check: No progress tracking
Validate with people who use this workflow before building.
Hypothesis 4
Consider a freemium model with a trial period.
Assumption to check: High price point with no trial
Validate with people who use this workflow before building.
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
react-navigation
expo-haptics
@react-native-community/async-storage
react-native-svg
BUILD KIT DIFFICULTY
Intermediate
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.
