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
Howbout: shared calendar
The shared calendar for friends, couples, and family
Free · In-app purchases
PRICE
Free
In-app purchases
BUSINESS MODEL
Freemium
No overall Grossing estimate available
RATING
★ 4.8
50,015 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 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.
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 Howbout: shared calendar: map the core Social Networking 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
Implement smart suggestions based on availability.
Assumption to check: Users find it hard to coordinate multiple schedules effectively.
Validate with people who use this workflow before building.
Hypothesis 2
Allow users to customize notification preferences.
Assumption to check: Event notifications can be overwhelming.
Validate with people who use this workflow before building.
Hypothesis 3
Provide options to sync with Google Calendar, iCal, etc.
Assumption to check: Lack of integration with other calendar apps.
Validate with people who use this workflow before building.
Hypothesis 4
Enhance messaging capabilities with media sharing and reactions.
Assumption to check: Limited chat features for event discussions.
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
The shared calendar for friends, couples, and family This is the app you’ve seen all over TikTok. 10M downloads, 200M+ plans made, and 1B+ views across social media. Howbout is how millions of people actually see each other more. Planning shouldn't take a hundred messages and a "when works for you?" thread that goes nowhere. Howbout fixes that. Find the gap, lock in the plan, actually see the people who matter to you. … WHAT YOU CAN DO WITH HOWBOUT SEE WHEN EVERYONE'S FREE No guessing, it's right there on the calendar. MAKE PLANS Add events, add details, and keep everything together, so plans don't fall apart. SHARE YOUR CALENDAR OR AVAILABILITY Choose what people see. Stay private or share with friends. KEEP ALL THE DETAILS IN ONE PLACE Plans, chats, locations, notes, photos… no switching apps or losing the details. REAL TIME NOTIFICATIONS Get updates when plans change or when your friends are up to something fun. MAKE YOUR CALENDAR YOURS Color-code and customize your calendar how you like. SYNC YOUR CALENDARS & TIMELINES Work, school, personal, social… it's all in one place, so nothing clashes. UP NEXT WIDGETS Stay on top of your upcoming plans and see what your friends are up to from your home screen. … BUILT FOR REAL LIFE For friend groups: check availability, lock in plans, actually see each other more. For couples: stay in sync, plan dates faster, stop double-booking each other. For families: track school runs, appointments, and weekends, all in one place. … HOWBOUT+ Unlock more customization like colors and app themes, smarter planning tools, and get an all around better experience. Your subscription will automatically renew unless turned off at least 24 hours before the end of the current period. You can manage your subscription in your App Store settings. … Contact us: [email protected] · Follow @howbout_app Privacy: howbout.app/privacy · Terms: howbout.app/terms
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
@supabase/supabase-js
react-native-paper
react-navigation
BUILD KIT DIFFICULTY
Expert
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.
