Five prototypes in one day
On day one, my co-founder tested five clickable prototypes. Her words replaced ours, and by the evening the MVP was cut down to five screens and eight journeys.
Day 1 5 prototypes tested · MVP: 5 screens, 8 journeys
My own product · Method · 2026
From idea to an app on my iPhone in 12 days.
This is the app I am building with a co-founder who is a professional model. This page covers the method: how it went from an idea to a working app, with a brand, a filed trademark and a tested security base, in about seven working days. Then how that method became a guide for the next app.
RoleFounder and product owner. Code written with Claude
Timeline25 Sept to 6 Oct 2026
StackClaude, Figma, Expo, Supabase, Vercel, GitHub
ScopeBrand, trademark, design system, security base, first app batches, website
12 daysFrom the idea to an app on iPhone, a filed trademark and a method
≈ 56 hOf my time on the app, plus about 30 h on the website
≈ 80Pull requests, about ten of them deliberate counter-tests
Context
A product of my own, built with Claude.
My co-founder knows the work of a professional model from the inside. I bring product, brand and build. Claude researches, drafts and writes the code.
The product stays private until launch. What I can share is how we work, because that part is reusable.
The challenge
Go fast, with security first.
Brand, trademark, design, accounts, legal and code, in about seven working days of my time.
With one rule set on day four and kept since: security comes first, and every protection is proven by a test.
The system
A launch method in ten phases.
The app was built one way. That way is now a guide and a starter kit for the next app.
Day one
Project rules, a decision log and the security rule go in before any work.
In parallel
Product, brand, accounts and legal run side by side, in the order their dependencies allow.
Proof at every step
Each batch is tried on a real phone and closes with a proof sheet.
Day one kit
Project rulesRoles and when to ask
Decision logEvery choice, dated
Security firstRule no. 1
Copied into every new project
Product
5 prototypesTested in one day
A simpler MVP5 screens, 8 journeys
Design systemThen 18 screens
With the domain expert
In parallel
Name, then logoChecked before identity
Slow sign-ups earlyChecked after 48 h
TrademarkFiled on day 11
Legal and GDPR in the background
Build
Small batchesBlocking checks
Counter-testsTests that can fail
On my iPhoneEvery batch tried
About 80 pull requests
12 daysFrom idea to app
56 hOn the app, about 7 working days
80Pull requests, approximately
10Phases in the method
ClaudeFigmaExpoSupabaseGitHub
The ten phases
- 1Idea and market
- 2Name and brand
- 3Accounts and slow sign-ups
- 4Product and MVP
- 5Identity and design
- 6Technical choices
- 7Legal and GDPR
- 8Build and tests
- 9Beta and launch
- 10After the launch
What I built
Four habits that made it fast.
Every decision written down
A dated log where each decision gives its reason and names the one it replaces. 180 decisions in the first twelve days, so any session can pick up without re-explaining.
D5825 SeptMVP cut to 5 screens and 8 journeysD7428 SeptRule no. 1: security firstD10229 SeptA real app on the stores replaces the web appD1524 OctChecks run only when their code changesSecurity with proof
Each batch closes with a proof sheet. A counter-test breaks a protection on purpose to check that the test catches it; about ten were closed without merging. The AI has no access to production.
Break a protection on purpose
The test must fail
Closed without merging, protection proven
Clear roles
Claude prepares and writes. I decide, create the accounts and press the final button in production. My co-founder brings the craft and tests the app.
MeDecide, create accounts, ship to production
Co-founderProfessional model: the craft, the words, the tests
ClaudeResearch, drafts and all of the code
Results
An app on my phone, and a method for the next one.
On day twelve, a retrospective turned the project into a ten-phase guide and a starter kit.
Day 9First batch of the app running on my iPhone
Day 11The trademark filed
Day 12Method v1: a ten-phase guide and a day-one kit
Stack
Tools and how I used them
Working with AIClaude project, CLAUDE.md, decision log
PrototypesClickable, built with Claude
DesignFigma, then exported for the code
AppExpo (React Native)
Back endSupabase, Vercel, Sentry
CodeGitHub, protected branch, blocking checks
WebsiteProduct website, about 30 hours
The method
What the next app starts with
▤A guide in ten phasesIdea to after launch
▤A day-one kitRules, logs, account setup list
✓A rule for when to stop and ask5 criteria
▤Known issues and their fixesShared across projects
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