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
PreGrade Ultra
PreGrade Ultra uses perspective correction to reduce the impact of camera angle on your centering measurements.
Free · In-app purchases
PRICE
Free
In-app purchases
BUSINESS MODEL
Freemium
No overall Grossing estimate available
RATING
★ 5.0
2 ratings · Top 5%
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 included18 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 PreGrade Ultra: map the core Developer Tools 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
Introduce advanced analytics for better insights.
Assumption to check: Limited analytics features for academic performance tracking.
Validate with people who use this workflow before building.
Hypothesis 2
Implement a cleaner, more organized settings page.
Assumption to check: Cluttered UI for settings options.
Validate with people who use this workflow before building.
Hypothesis 3
Add push notifications for grade entry reminders.
Assumption to check: No reminders for grade entries.
Validate with people who use this workflow before building.
Hypothesis 4
Allow users to export grades to CSV or PDF.
Assumption to check: No option for exporting grades.
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
PreGrade Ultra uses perspective correction to reduce the impact of camera angle on your centering measurements. **PERSPECTIVE CORRECTION** Other centering apps measure your photo as-is. If your camera is even slightly angled, your measurements can lose accuracy. PreGrade Ultra uses homography-based perspective correction to mathematically flatten your card to its true 63×88mm dimensions before measuring borders — centering analysis powered by computer vision. **PRECISION CENTERING ANALYSIS** - Measure left/right and top/bottom centering ratios - Millimeter-level border measurements - Front and back analysis with separate thresholds - Visual edge detection confirms your guide placement - Detect clockwise and counterclockwise print tilt **7 GRADING COMPANIES** Centering grades from PSA, BGS, CGC, TAG, SGC, ACE, and AGS. Every company has different thresholds — see which grade your card may qualify for at each one, with full threshold breakdowns. **CROSS-GRADE OPPORTUNITIES** Already have a graded card? See which companies may give a higher centering grade. The Understand tab highlights your potential best market-value grade at a glance. **MARKET PRICING** Look up active eBay listings for any Pokémon card. See current asking prices for raw and graded cards across most major grading companies. **BUILT FOR COLLECTORS, NOT ADVERTISERS** No ads. No banner spam. PreGrade Ultra is a tool built by a collector, for collectors. 3 free grading sessions included. Unlock unlimited access with a one-time Pro upgrade. **IMPORTANT:** PreGrade Ultra measures centering only. Card grading involves surface condition, corners, edges, and print quality — factors that cannot be assessed from a photo. Results are estimates and are not guaranteed to match any grading company's official assessment. PreGrade Ultra is not affiliated with, endorsed by, or sponsored by any grading company. Pokémon is a trademark of Nintendo, Creatures Inc., and GAME FREAK Inc. eBay is a trademark of eBay Inc. All company names and grading scales are trademarks of their respective owners.
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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
React Native
Expo
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axios
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expo-notifications
BUILD KIT DIFFICULTY
Advanced
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.
