Application development

App developmentiOS, Android & Web

Your business deserves more than a spreadsheet and a group chat. We build apps that centralise your workflow, serve your clients, and grow with you, custom-built or white-label.

What we deliver

Full-stack applications built to your exact specifications, from first screen to app store.

iOS & Android

Native-quality apps on both platforms. One codebase, two stores, no compromise on speed or experience.

Web Applications

Full-featured web apps accessible from any browser. Responsive, installable, and always up to date.

Custom UI/UX

Every screen designed around your users. Intuitive flows, clean layouts, and a look that matches your brand.

Secure & Reliable

Authentication, data encryption, and role-based access built in from day one. Your users' data stays safe.

Real-Time Features

Live messaging, instant notifications, synced dashboards. Your app reacts the moment something happens.

Admin Dashboards

A back-office that gives you full control: users, content, analytics, revenue. All in one place.

How we build it

From your idea to a live product in four phases.

  1. 1

    Discovery & Scope

    We map your workflow, your users, and your goals. We define exactly what the app needs to do and how people will use it.

  2. 2

    Design & Prototype

    Interactive mockups for every screen. You test the flow before a single line of code is written, and we iterate until it feels right.

  3. 3

    Development & Testing

    We build in sprints: each cycle delivers working features you can review. Real devices, real data, real feedback loops.

  4. 4

    Launch & Iteration

    Store submission, deployment, onboarding. Then: analytics, user feedback, and continuous improvements post-launch.

Our own product

My Coach

We designed and keep developing My Coach, the app for independent fitness coaches: programs, check-ins, messaging, scheduling and revenue tracking, all in one place. Their clients get their own app; coaches get their time back.

My Coach
Visit mycoach-app.fr

Used daily by independent coaches since the beta.

Program Builder

Coaches create, edit, and publish workout programs. Clients see the latest version instantly.

Built-in Messaging

Direct chat between coach and client. Progress photos, questions, and follow-ups in one thread.

Smart Scheduling

Clients see available slots and book directly. Coaches get notified, no back-and-forth.

Progress Tracking

Every check-in feeds the charts automatically. Weight, measurements, and goals over time.

Revenue Dashboard

Who paid, who is late, how much is coming next month. One screen, zero guesswork.

Client Workspace

Each client gets their own space: programs, check-ins, messages, nutrition — all in one view.

Before & after

A coach following thirty people doesn't lose time coaching. They lose it between tools.

Update a training program

Without

Re-open the spreadsheet, re-export, re-send, hope the right version gets read

With My Coach

Edit and publish — the client sees the new version immediately

Book a session

Without

Six messages to find a slot that works for both

With My Coach

Client sees your availability, books, you get notified

Find a weight from three months ago

Without

Scroll through message history for ten minutes

With My Coach

Open their profile — the chart has every check-in

Know who hasn't paid this month

Without

Cross-reference a notebook and bank statements

With My Coach

Late payments are listed, reminders sent in one click

Send a weekly check-in

Without

Copy the same questionnaire, message each client one by one

With My Coach

Pick the template and recipients, send in one gesture

Why choose us

What you get when Genesy.X builds your app.

  • A single app for iOS, Android, and web — consistent experience everywhere
  • Your brand identity in every pixel, no generic templates
  • Real-time sync: messaging, notifications, live data
  • Secure authentication and role-based access for every user type
  • Admin dashboard to manage content, users, and revenue
  • Built to scale as your user base grows
  • Post-launch support, updates, and new feature development
  • Custom-built or white-label — whichever fits your timeline and budget

Our work

Projects we have shipped

Websites and platforms built for real businesses, each one designed from scratch.

BaseTrustCapital

BaseTrustCapital

Trading · Python backend · Client area

More than a trading website: a complete investing ecosystem. Each client gets a secure dashboard to monitor portfolios, track strategies and follow live data powered by Python backend servers.

Izuka

Izuka

Fitness · Client & admin areas · Custom build

More than a fitness website: a complete online coaching system. Clients get their programs, nutrition plans, progress tracking and messaging; the coach runs everything from a dedicated admin space.

Léna Cullerier

Léna Cullerier

Home help · Business website · Local SEO

A professional showcase that doubles as a lead-generation tool for home-help services: one page per service, quote requests connected to a database, and advanced local SEO.

Ready to build your app?

Tell us about your project. Free discovery call, no commitment: we help you figure out the right approach for your idea.