01 · Web
Websites & web apps
Conversion-focused landing pages, business platforms and fast, accessible SaaS products built to evolve.
Product studio · Web, mobile & AI
A senior team turning ideas and business needs into high-performing websites, mobile apps and useful AI solutions — without big-agency overhead.
A human reply within 24 hours · No-obligation first call
Free audit
30 seconds to start the audit. You receive a full 5-dimension report by email, signed 404-DEV, INC.
Report signed 404-DEV, INC. · No access to your site required · Read-only
What we build
No unnecessary sales layer: you work directly with the people designing and building your product.
01 · Web
Conversion-focused landing pages, business platforms and fast, accessible SaaS products built to evolve.
02 · Mobile
One modern foundation for both stores, fast iteration and a polished native-feeling experience.
03 · AI
Agents, automation and augmented search that reduce repetitive work and create a measurable advantage.
Clients & work
E-commerce, real estate, hospitality, fintech and logistics — experience spanning major brands and early-stage products.
Selected work & collaborations
Fintech · Mobile
Proptech · Web + Mobile
Hospitality · Web
Luxury · Mobile
Detailed before/after metrics available on request, with the client’s consent.
A straightforward process
Goals, users, scope and budget: the shortest route to meaningful first value.
Journey, interface and architecture are shaped together to avoid surprises.
Visible progress, frequent demos and quick decisions with your team.
Production release, measurement and ongoing support guided by real feedback.
Senior talent, lean overhead
Our lean setup keeps your budget focused on the product. You get an experienced team, transparent scope and technical choices shaped around your reality — not our billing model.
Frequently asked
Straight answers, no jargon. Missing a question? Email us and a developer will reply.
A compact senior team puts your budget into design and code, not into sales and management layers. You talk directly to the three developers and the designer who build the product, which speeds up decisions and avoids misunderstandings.
We set a performance budget at design time: Largest Contentful Paint must stay under 2.5 seconds, Google’s “good” Core Web Vitals threshold. Accessibility is tested automatically with axe-core, then checked by hand against WCAG 2.2 level AA.
AI cuts costs when it handles repetitive, high-volume tasks: email triage, data entry, document extraction, first-line answers. We connect large language models (LLMs) to your tools with n8n workflows or custom code, and a human approves sensitive decisions.
The audit analyses the public page of your choice across five dimensions and emails you a report signed 404-DEV, INC. It needs no access to your site and changes nothing: it reads the page like a visitor.
With React Native and Expo, one codebase produces both the iOS and Android apps, which lowers development and maintenance costs. Screens stay native, and we write platform-specific code when the product needs it.
The price depends on scope: number of screens, integrations, platforms and level of automation. After a free first call, we send a clear estimate split into stages, so you launch what creates value first.
Yes. We audit the code and infrastructure, stabilise what needs it, then extend the product. When a focused rebuild is more responsible than a rewrite, we recommend it.
We work remotely with clients in France, Belgium, Switzerland, Luxembourg, Canada and the United States. We work in English or French.
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Have a product in mind?
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