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
Winmail.dat Opener Pro
winmail.dat opener pro opens winmail.dat (tnef), .msg, and .oft outlook email attachments on iphone and ipad with a one-time purchase — no subscriptions.
$0.99 · In-app purchases
PRICE
$0.99
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's included16 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 Winmail.dat Opener Pro: map the core Utilities 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
Implement efficient file handling and loading indicators.
Assumption to check: Difficulty in opening large winmail.dat files
Validate with people who use this workflow before building.
Hypothesis 2
Add more sharing options and integrations with other apps.
Assumption to check: Limited sharing options for file content
Validate with people who use this workflow before building.
Hypothesis 3
Expand functionality to open other common file types.
Assumption to check: No support for multiple file formats
Validate with people who use this workflow before building.
Hypothesis 4
Add toast notifications and visual feedback for actions.
Assumption to check: Lack of user feedback on actions
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
winmail.dat opener pro opens winmail.dat (tnef), .msg, and .oft outlook email attachments on iphone and ipad with a one-time purchase — no subscriptions. works fully offline with 100% on-device processing for maximum privacy. multilingual support has been upgraded and optimized for fast, secure file access. tired of “free” apps that lock basic features behind subscriptions? hate paying monthly just to open an email attachment? winmail.dat opener pro is a pay-once, own-forever solution. no subscriptions. no trials. no recurring fees. the app safely unpacks outlook winmail.dat (tnef) files and opens .msg and .oft files directly on your device. all processing happens on-device, so your emails and attachments never leave your phone. key features: • one-time purchase. own it forever. • open winmail.dat (tnef), outlook .msg, and .oft files. • extract attachments including photos, pdfs, word, and excel files. • 100% on-device processing for maximum privacy. • optimized for the latest ios with dark mode and drag & drop. • multilingual support fully upgraded and optimized. supported formats: •winmail.dat (tnef) •outlook message (.msg) •outlook template (.oft) how to use: 1. open the mail app or files app. 2. tap the attachment (winmail.dat, .msg, or .oft). 3. select share and choose winmail.dat opener pro. 4. view, print, or save your files instantly. no subscriptions. no tracking. no cloud uploads. just open your files — fast, private, and forever. we update regularly to ensure compatibility with the latest ios versions. if you have any questions or feedback, feel free to contact us anytime.
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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
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.
