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.
billingsMentor® guides you in observing, recording and interpreting your fertility symptoms according to the Billings Method
$4.99 · 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.
First kit free with a verified email
Combine features and design from your favorite apps.
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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.
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Good fit for mobile-first iOS and Android prototypes with managed app scaffolding.
Rork plan preview for billingsMentor®: 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.
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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 user engagement features (1 star rating).
Validate with people who use this workflow before building.
Hypothesis 2
Assumption to check: Lack of customization options for tracking.
Validate with people who use this workflow before building.
Hypothesis 3
Assumption to check: Poor onboarding experience.
Validate with people who use this workflow before building.
Hypothesis 4
Assumption to check: Inconsistent performance and bugs.
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.
billingsMentor® guides you in observing, recording and interpreting your fertility symptoms according to the Billings Method. It can be used to achieve or avoid pregnancy. Cycles do not have to be regular. It helps you to follow the Billings Method by: • guiding you in making a proper recording of your fertility symptoms; • automatically generating your fertility chart; • interpreting your symptoms and your fertility status on each day; • recognizing your Peak day in a cycle and predicting menstruation; • allowing you to override and mark your Peak day in a cycle; • identifying your Basic Infertile Pattern (BIP) whether you are having normal cycles or long cycles (e.g. breastfeeding); • allowing you to override and define your Basic Infertile Pattern (BIP); • applying the 1,2,3 count of the rule concerning a change from the BIP before the Peak day; • reminding you of the wait day after intercourse during the pre-Peak phase. The underlying fertility interpreter (Ovulation Mentor) is ranked the most accurate of all fertility awareness apps analyzed in this study: http://www.jabfm.org/content/29/4/508.full.pdf+html English, Spanish, French, Portuguese, Russian, Chinese and Arabic versions are contained in the one download. billingsMentor® avoids the use of stamps and symbols in the fertility chart by visualising fertility as a simple bar chart that combines fertility with the rules of the Billings Method. This format is intuitive for the new user. There is an option to use the traditional stamp or symbol format if desired. Tablet users: Users should consider using the web interface from tablets (see below). billingsMentor® is also available as a web service. All data, whether submitted from mobile, tablet or desktop is stored on the billingsMentor® server. Thus your current fertility chart is always available from mobile or internet and is recoverable in the case of a lost or stolen phone. When you begin to use the service, you make a privacy agreement. Reference: The Billings Method, by Dr Evelyn Billings and Dr Ann Westmore, Penguin Books, first published 1980, new edition 2011.
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.
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.