# 🚀 How to Run the VQA Mobile App

## Quick Overview

You now have a complete React Native mobile app for Visual Question Answering! Here's what was created:

### ✅ What's Built

1. **Backend API** (`backend_api.py`)
   - FastAPI server wrapping your ensemble VQA models
   - Automatic routing between base and spatial models
   - Image upload and question answering endpoints

2. **Mobile App** (`ui/` folder)
   - Beautiful React Native app with Expo
   - Google OAuth authentication
   - Camera and gallery image picker
   - Question input and answer display
   - Model routing visualization

## 🎯 Running the App (3 Steps)

### Step 1: Start the Backend Server

```bash
# Open PowerShell/Terminal
cd c:\Users\rdeva\Downloads\vqa_coes

# Install API dependencies (FIRST TIME ONLY)
# If you get import errors, run this:
pip install fastapi uvicorn python-multipart

# Start the server
python start_backend.py
# Or: python backend_api.py
```

> **Note**: If you get "ModuleNotFoundError", see [IMPORT_ERRORS_FIX.md](file:///c:/Users/rdeva/Downloads/vqa_coes/IMPORT_ERRORS_FIX.md) for solutions.

✅ **Keep this window open!** The server must stay running.

You should see:
```
🚀 INITIALIZING ENSEMBLE VQA SYSTEM
✅ Ensemble ready!
```

### Step 2: Configure the Mobile App

1. **Find your local IP address:**
   ```bash
   ipconfig
   ```
   Look for "IPv4 Address" (e.g., `192.168.1.100`)

2. **Update the API URL:**
   - Open: `ui\src\config\api.js`
   - Change line 8:
     ```javascript
     export const API_BASE_URL = 'http://YOUR_IP_HERE:8000';
     ```
   - Example:
     ```javascript
     export const API_BASE_URL = 'http://192.168.1.100:8000';
     ```

### Step 3: Start the Mobile App

```bash
# Open a NEW PowerShell/Terminal window
cd c:\Users\rdeva\Downloads\vqa_coes\ui

# Start Expo
npm start
```

You'll see a QR code in the terminal.

### Step 4: Run on Your Phone

1. **Install Expo Go** on your smartphone:
   - [Android - Play Store](https://play.google.com/store/apps/details?id=host.exp.exponent)
   - [iOS - App Store](https://apps.apple.com/app/expo-go/id982107779)

2. **Scan the QR code:**
   - Android: Open Expo Go → Scan QR
   - iOS: Open Camera → Scan QR → Tap notification

3. **Wait for the app to load** (first time takes ~1-2 minutes)

## 📱 Using the App

### Option A: Test Without Google Login

For quick testing, you can bypass Google authentication:

1. Open `ui\App.js`
2. Find line 23-27 and replace with:
   ```javascript
   <Stack.Screen name="Home" component={HomeScreen} />
   ```
3. Save and reload the app (shake phone → Reload)

### Option B: Set Up Google Login

1. Go to [Google Cloud Console](https://console.cloud.google.com/)
2. Create a new project
3. Enable Google+ API
4. Create OAuth 2.0 credentials
5. Update `ui\src\config\google.js` with your client IDs

### Testing VQA Functionality

1. **Select an image:**
   - Tap "Camera" to take a photo
   - Tap "Gallery" to choose existing image

2. **Ask a question:**
   - Type your question (e.g., "What color is the car?")
   - Tap "Ask Question"

3. **View the answer:**
   - See the AI-generated answer
   - Check which model was used:
     - 🔍 **Base Model** - General questions
     - 📍 **Spatial Model** - Spatial questions (left, right, above, etc.)

## 🧪 Example Questions to Try

### General Questions (Base Model 🔍)
- "What color is the car?"
- "How many people are in the image?"
- "What room is this?"
- "Is there a dog?"

### Spatial Questions (Spatial Model 📍)
- "What is to the right of the table?"
- "What is above the chair?"
- "What is next to the door?"
- "What is on the left side?"

## 🔧 Troubleshooting

### "Cannot connect to server"
- ✅ Check backend is running (`python backend_api.py`)
- ✅ Verify IP address in `api.js` matches your computer's IP
- ✅ Ensure phone and computer are on the **same WiFi network**
- ✅ Check Windows Firewall isn't blocking port 8000

### "Model not loaded"
- ✅ Ensure these files exist in `c:\Users\rdeva\Downloads\vqa_coes\`:
  - `vqa_checkpoint.pt`
  - `vqa_spatial_checkpoint.pt`
- ✅ Check backend terminal for error messages

### App won't load on phone
- ✅ Verify Expo Go is installed
- ✅ Both devices on same WiFi
- ✅ Try restarting Expo: Press `Ctrl+C`, then `npm start`
- ✅ Clear cache: `npm start -- --clear`

### Camera/Gallery not working
- ✅ Grant permissions when prompted
- ✅ Check phone Settings → App Permissions

## 📁 Project Structure

```
vqa_coes/
├── backend_api.py              # FastAPI backend server
├── ensemble_vqa_app.py         # Your existing ensemble system
├── model_spatial.py            # Spatial model
├── models/model.py             # Base model
├── vqa_checkpoint.pt           # Base model weights
├── vqa_spatial_checkpoint.pt   # Spatial model weights
├── requirements_api.txt        # Backend dependencies
├── QUICK_START.md             # This guide
└── ui/                        # Mobile app
    ├── App.js                 # Main app component
    ├── app.json               # Expo configuration
    ├── package.json           # Dependencies
    └── src/
        ├── config/
        │   ├── api.js         # ⚠️ UPDATE YOUR IP HERE
        │   └── google.js      # Google OAuth config
        ├── contexts/
        │   └── AuthContext.js # Authentication
        ├── screens/
        │   ├── LoginScreen.js # Login UI
        │   └── HomeScreen.js  # Main VQA UI
        ├── services/
        │   └── api.js         # API client
        └── styles/
            ├── theme.js       # Design system
            └── globalStyles.js
```

## 📚 Documentation

- **Quick Start**: `QUICK_START.md` (this file)
- **Full README**: `ui/README.md`
- **Implementation Details**: See walkthrough artifact

## 🎨 Customization

### Change Colors
Edit `ui/src/styles/theme.js`:
```javascript
colors: {
  primary: '#6366F1',    // Change to your color
  secondary: '#EC4899',  // Change to your color
  // ...
}
```

### Change App Name
Edit `ui/app.json`:
```json
{
  "expo": {
    "name": "Your App Name",
    "slug": "your-app-slug"
  }
}
```

## 🚢 Next Steps

Once everything works:

1. **Add Google OAuth** for production
2. **Create custom icons** (see `ui/assets/ICONS_README.md`)
3. **Build standalone app**:
   ```bash
   npx eas-cli build --platform android
   ```

## 💡 Tips

- **Backend must run first** before starting the mobile app
- **Same WiFi network** is required for phone and computer
- **First load is slow** - subsequent loads are faster
- **Shake phone** to access Expo developer menu
- **Check logs** in both terminals for debugging

## 🆘 Need Help?

1. Check the troubleshooting section above
2. Review backend terminal for errors
3. Check Expo console in terminal
4. Verify all configuration steps

---

**Ready to test?** Follow the 4 steps above and start asking questions about images! 🎉