The latest articles on DEV Community by Hasibul Hasan (@hasibul_hasan_dc49862fa65). https://dev.to/hasibul_hasan_dc49862fa65 https://media2.dev.to/dynamic/image/width=90,height=90,fit=cover,gravity=auto,format=auto/https:%2F%2Fdev-to-uploads.s3.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F3827696%2F700847e5-8dfe-4b25-b2c1-b55dd70002cc.png https://dev.to/hasibul_hasan_dc49862fa65 en Hasibul Hasan Mon, 16 Mar 2026 16:34:44 +0000 https://dev.to/hasibul_hasan_dc49862fa65/how-i-built-an-ai-powered-habit-tracker-with-react-native-gemini-18hd https://dev.to/hasibul_hasan_dc49862fa65/how-i-built-an-ai-powered-habit-tracker-with-react-native-gemini-18hd <p>I'm a solo developer from Bangladesh, and I just shipped HabitFlow — a habit tracker with an AI coach built on Google's Gemini.</p> <h2> Why I built it </h2> <p>I kept losing long streaks when I got sick or busy. Every habit app I tried treated a missed day as failure. So I built one with <strong>streak freezes</strong> — your streak stays alive on off days.</p> <p>Then I thought: what if the app could actually coach you? So I added an <strong>AI Habit Coach</strong> powered by Gemini that analyzes your real completion data and gives personalized advice.</p> <h2> Tech Stack </h2> <ul> <li> <strong>React Native</strong> + <strong>Expo</strong> (managed workflow)</li> <li> <strong>Firebase</strong> — Auth, Firestore, Analytics</li> <li> <strong>Google Gemini Flash</strong> — AI coaching</li> <li> <strong>RevenueCat</strong> — subscriptions</li> <li> <strong>Zustand</strong> — state management with offline-first persistence</li> </ul> <h2> Key Features </h2> <ul> <li>Daily/weekly habit tracking with streaks</li> <li>Multi-count habits (e.g., "Drink water 8x" with tap-to-increment)</li> <li>AI Coach that knows your actual habit data</li> <li>Time-bound challenges (7-90 days)</li> <li>Focus timer (Pomodoro) linked to habits</li> <li>Calendar heatmap &amp; analytics</li> <li>Streak freezes</li> <li>Decline alerts when consistency drops</li> </ul> <h2> Challenges I Faced </h2> <ul> <li>Firebase JS SDK doesn't support Analytics on React Native — had to use the native <code>@react-native-firebase/app</code> SDK</li> <li>Gemini's Firebase AI SDK uses <code>DOMException</code> which doesn't exist in React Native — switched to REST API</li> <li>Syncing local-first Zustand stores with Firestore real-time listeners without infinite loops</li> </ul> <h2> Try it </h2> <p><a href="https://play.google.com/store/apps/details?id=com.hasib.habitflow" rel="noopener noreferrer">https://play.google.com/store/apps/details?id=com.hasib.habitflow</a></p> <p>Would love feedback from the dev community. What would you add next?</p> reactnative android ai productivity