Sérein — Wellness mobile app

Context

Sérein is a concept mobile app, built to demonstrate a skill different from my web projects: native cross-platform development. The goal — a wellness app, calm and minimal, that makes you want to come back every day.

The demo opens in a browser, shown inside a phone frame: it really is a mobile app, not a website.

Goals

• Prove a command of React Native / Expo, the reference mobile stack.
• Deliver a native experience on each platform, not a lowest common denominator.
• Go beyond the mockup: an app that is genuinely usable, with persistent state and a complete flow.

Solution

Four screens designed as a daily ritual:

• Today — the day's habits, a progress ring, current streaks, and a floating button to create a habit.
• Create a habit — a modal sheet with icon picker (organised grid), colour picker and live preview: nothing generic.
• Breathe — an animated heart-coherence exercise (5s / 5s), paced by a light haptic feedback.
• Progress & Profile — a grid of the last 7 days, best streak, and a customisable profile (first name, avatar) created right at onboarding.

A native experience, per platform

• iOS — SF Symbols icons, Liquid Glass tab bar, Taptic Engine.
• Android — Material icons, native vibrations.
• Everywhere — refined typography, micro-animations (Reanimated), and a fully offline operation: data stays on the device, no server.

Stack

React Native + Expo (expo-router), Reanimated animations, AsyncStorage local storage, static web export deployed on Vercel. One codebase, three targets.