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
Big Day - Event Countdown
Are you looking for widgets to track your events? Here is the widget app to help you see your events on your Home Screen at a glance
$0.99 · In-app purchases
PRICE
$0.99
In-app purchases
BUSINESS MODEL
Paid
No overall Grossing estimate available
RATING
★ 4.2
58 ratings · Top 30%
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 included17 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.
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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 Big Day - Event Countdown: map the core Lifestyle 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
Allow users to choose event colors, icons, and themes.
Assumption to check: Limited customization options for events
Validate with people who use this workflow before building.
Hypothesis 2
Implement push notifications to remind users of their events.
Assumption to check: No notifications for upcoming events
Validate with people who use this workflow before building.
Hypothesis 3
Provide clear explanations and benefits of each subscription tier.
Assumption to check: Subscription model can be confusing
Validate with people who use this workflow before building.
Hypothesis 4
Enable users to share events on social media or with friends directly.
Assumption to check: Lack of social sharing features
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
Are you looking for widgets to track your events? Here is the widget app to help you see your events on your Home Screen at a glance. Are you bored with the other countdown or day tracking apps which have only text, small images? We have a totally different and unique app with full graphics and animation effects. Or are you tired of too complicated user interfaces with other apps? We have an easy-to-use app focusing on the basics. Big Day is a day tracking app and widget which tells you the remaining days until or starts counting the days after the event with your own photos. It is the simplest and the most beautiful way to track your big days. When to use Big Day : - Your wedding day, valentine's day, the first date, birthday, anniversary, the birth of your children and baby, holiday, meeting, trip, party, vacation, discharge, exam, days of quitting smoking, graduation, halloween, new year, thanksgiving and all of the other very important days of your life. Features: - Widgets on your home screen. - No annoying ads banner. - Select your own pictures for the background. - Share your big day on Facebook, Instagram, Twitter or other social apps. - Set notification date and time to get an alarm. - Change color by double-tapping the counter frame. - Multiple dates and events up to 30. - Reorder dates and events. - View all events in a list. Contacts/Downloads : To contact us or download some sample photos on the screenshot, Please visit at http://bigdayapp.com/
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
React Native
Expo
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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.
