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
f8 Lens Toolkit
f8 is the fastest and easiest tool for all photographic calculations: Effortlessly find corresponding focal lengths & apertures for different formats, calculate depth of field (DOF), and find field of view for any cam...
$9.99 · In-app purchases
PRICE
$9.99
In-app purchases
BUSINESS MODEL
Paid
No overall Grossing estimate available
RATING
★ 4.9
26 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.
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 included18 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 f8 Lens Toolkit: map the core Photo & Video 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
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
Include advanced editing tools like AI enhancements and custom filters.
Assumption to check: Limited editing features compared to competitors
Validate with people who use this workflow before building.
Hypothesis 2
Simplify UI by grouping related features and using a cleaner layout.
Assumption to check: Cluttered interface with too many options
Validate with people who use this workflow before building.
Hypothesis 3
Introduce a freemium model with essential features free and premium features unlocked through subscription.
Assumption to check: High subscription cost compared to other apps
Validate with people who use this workflow before building.
Hypothesis 4
Integrate easy sharing to social media directly from the app.
Assumption to check: Lack of social sharing options
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
f8 is the fastest and easiest tool for all photographic calculations: Effortlessly find corresponding focal lengths & apertures for different formats, calculate depth of field (DOF), and find field of view for any camera and lens. The sensor comparison and lens coverage tool make this app complete. ◈◈◈ Get professional-grade features & the most intuitive user-interface in its class ◈◈◈ No matter if you are a seasoned pro or a film/photography student, f8 has got you covered. It’s packed with the tools you need and highly customizable to deliver precise calculations for any setup imaginable. It has been proven to be an indispensable tool on any shoot. f8 comes with: • Depth of Field & Hyperfocal Distance Calculator • Field of View Calculator • Lens Matcher: Equivalent Focal Length & F-Stop • Camera Sensor Comparison Tool • Lens Coverage Tool • Thousands of cameras & lenses included • Close Focus & Aperture data for most lenses • Supports anamorphic shooting & Metabones Speedboosters f8 is the perfect companion app and reference tool for Photographers, Cinematographers, Camera Operators, Camera Assistants (1.AC) & VFX Supervisors. ◈◈◈ Download f8 now and have a precise optical toolkit at your fingertips ◈◈◈ ◆ CINE CAMERAS ◆ AJA Cion ARRI Alexa 35, Alexa 65, Alexa Classic, Alexa LF, Alexa Mini, Alexa Mini LF, Alexa SXT, Alexa XT, Amira, D-21 Blackmagic Cinema Camera, Micro Cinema Camera, Micro Studio Camera 4K, Pocket Cinema Camera, Pocket Cinema Camera 4K, Pocket Cinema Camera 6K, Pocket Cinema Camera 6K Pro, Production Camera 4K, Studio Camera 4K, Studio Camera HD, URSA, URSA (Broadcast), URSA 4.6K, URSA Mini 4.6K, URSA Mini 4K, URSA Mini Pro, URSA Mini Pro 12K, URSA Mini Pro 4.6K G2 Canon C100, C100 Mark II, C200, C300, C300 Mark II, C300 Mark III, C500, C500 Mark II, C70, C700 DJI Zenmuse X7 Film 16mm, 35mm, 65mm/70mm, 8mm Freefly Systems Wave Generic Broadcast Ikonoskop A-cam dII Kinefinity KineMAX, KineMini, Mavo, Mavo Edge, Mavo LF, TERRA Panasonic AF101, BGH1, EVA1, HDX 900, VariCam 35, VariCam LT Panavision DXL, DXL2, Genesis Phantom 65, Flex, Flex4K, HD GOLD, Miro LC321S, v2640 ONYX, VEO4K-PL PS-CAM X35 RED Dragon-X, Epic Dragon, Epic-W (Helium), Epic-X, Gemini, Komodo, Monstro-VV, One, Ranger (Gemini), Ranger (Helium), Ranger (Monstro), Raven, Scarlet-W (Dragon), Scarlet-X, Weapon (Dragon-VV), Weapon (Helium) Silicon Imaging SI-2K Sony F23, F3, F35, F5, F55, F65, F900, FS100, FS5, FS5 Mark II, FS7, FS7 Mark II, FS700, FX3, FX6, FX9, HDC-1500R, Venice Weisscam HS-2 Z CAM E2, E2-F6, E2-F8, E2-M4, E2-S6, E2G ◆ PHOTO CAMERAS ◆ Canon 1000D/XS, 100D, 10D, 1100D/T3, 1200D/T5, 1300D/T6, 1D, 1D C, 1D Mark II, 1D Mark III, 1D Mark IV, 1D X, 1D X Mark II, 1D X Mark III, 1Ds, 1Ds Mark II, 1Ds Mark III, 200D/SL2, 20D, 30D, 350D/XT, 400D/XTi, 40D, 450D/XSi, 500D/T1i, 50D, 550D/T2i, 5D, 5D Mark II, 5D Mark III, 5D Mark IV, 5DS, 600D/T3i, 60D, 650D/T4i, 6D, 6D Mark II, 700D/T5i, 70D, 750D/T6i, 760D/T6s, 77D, 7D, 7D Mark II, 800D/T7i, 80D, 850D/T8i, 90D, M50, R, R5, R6, Ra, RP Film (Still) 35mm (135), APS, Large Format, Medium Format, XPan Fujifilm GFX 100, GFX 100S, GFX 50R, GFX 50S, X-A7, X-H1, X-Pro2, X-Pro3, X-S10, X-T2, X-T200, X-T3, X-T4, X100V Hasselblad Digital Medium Format Leica CL, M10/M10-R, M8/M8.2, M9/M9-P, S, S2, SL, SL2, SL2-S Mamiya Leaf Credo Series Nikon D1, D100, D1H, D1x, D200, D2H, D2Hs, D2x, D3, D300, D3000, D300s, D3100, D3200, D3300, D3400, D3s, D3x, D4, D40, D40X, D4s, D50, D500, D5000, D5100, D5300, D5500, D5600, D60, D600, D610, D70, D700, D7000, D70s, D7100, D7200, D750, D7500, D80, D800, D810, D850, D90, DF, Z50, Z6, Z7 Olympus E Series Panasonic GH1, GH2, GH3, GH4, GH5, GH5S, S1, S1H, S1R, S5 Pentax 645D, 645Z, K Series Phase One Achromatic+, IQ Series, P 30+, P 40+, P 45+, P 65+ Sigma fp, fp L, SD1, SD15 Sony A290, A390, A450, A580, A6000, A6300, A6500, A6600, A7 III, A7C, A7r II, A7r III, A7r IV, A7s, A7s II, A7s III, A850, A9, A9 II, A900, A99, SLT-A37K, SLT-A57, SLT-A65, SLT-A77
Written user reviews are not shown here. Check current App Store reviews >
Screenshots
< Scroll to see more >
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
Zustand
axios
react-navigation
@react-native-community/slider
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.
