DementiaGuide AI

A modern iOS mobile application that acts as a digital library manager for dementia care information. Users can ask questions through text or voice and receive responses through a human-like avatar interface powered by NVIDIA ACE.

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Application Workflow

Rag Pipeline Workflow

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Video Walkthrough of our current Application

Screen.Recording.2026-04-29.at.1.24.15.PM.mov

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Overview

DementiaGuide AI is designed for caregivers, family members, and healthcare professionals. The app provides evidence-based dementia care guidance through a calm, accessible, and emotionally supportive interface. The AI avatar — Aria — responds in real time with natural speech, lip-sync, and expressive visual communication.

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Tech Stack

Layer	Technology
Framework	React Native (Expo SDK 54)
Navigation	React Navigation 7 (Bottom Tabs + Native Stack)
Avatar & Speech	NVIDIA ACE (Tokkio · Riva ASR/TTS · Audio2Face)
Animations	React Native Reanimated + Animated API
Gradients	expo-linear-gradient
Audio	expo-av
Haptics	expo-haptics
Safe Area	react-native-safe-area-context

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Screens

Screen	Description
Home	Avatar hero card, quick question chips, text/voice entry, navigation grid
Chat	iMessage-style conversation with bubble tails, typing indicator, suggestion chips
Library	Searchable knowledge base across 6 dementia-care categories
Voice	Full-screen voice UI with real-time waveform, state machine, and transcript
Settings	Accessibility controls — text size, contrast, audio, subtitles, haptics, privacy

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Project Structure

DementiaGuideAi/
├── App.js                          # Root entry point
├── babel.config.js
├── app.json                        # Expo config
├── src/
│   ├── navigation/
│   │   └── AppNavigator.js         # Bottom tab + stack navigator
│   ├── screens/
│   │   ├── HomeScreen.js
│   │   ├── ChatScreen.js
│   │   ├── LibraryScreen.js
│   │   ├── VoiceScreen.js
│   │   └── ProfileScreen.js
│   ├── components/
│   │   ├── Avatar.js               # Animated avatar (idle / listening / speaking)
│   │   ├── MessageCard.js          # Chat bubble with sources and actions
│   │   ├── CategoryCard.js         # Library category row
│   │   └── VoiceWaveform.js        # 9-bar animated waveform
│   ├── constants/
│   │   ├── colors.js               # Full design token palette
│   │   ├── typography.js           # Type scale and font config
│   │   └── data.js                 # Categories, resources, sample messages
│   └── services/
│       ├── aceService.js           # NVIDIA ACE integration (Tokkio stub)
│       └── knowledgeService.js     # Knowledge base search stub

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Getting Started

Prerequisites

• Node.js 20+
• Expo CLI
• Xcode (for iOS Simulator) or Expo Go on a physical device

Install

git clone <repo-url>
cd DementiaGuideAi
npm install

Run

# iOS Simulator
npx expo start --ios

# Android
npx expo start --android

# Clear Metro cache if needed
npx expo start --ios --clear

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NVIDIA ACE Integration

The avatar experience is powered by NVIDIA ACE (Avatar Cloud Engine). The integration architecture is documented in src/services/aceService.js.

Production pipeline:

User audio → Riva ASR → NIM LLM → RAG knowledge base
                                         ↓
                               Riva TTS + Audio2Face
                                         ↓
                              WebRTC avatar video stream

To connect a real ACE instance, set the following environment variables:

EXPO_PUBLIC_ACE_ENDPOINT=wss://your-tokkio-instance/v1/session
EXPO_PUBLIC_ACE_API_KEY=your-api-key

The service currently runs a mock response loop for development and testing.

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Design System

The UI follows iOS Human Interface Guidelines with a calm, accessible palette.

Token	Value	Use
Primary	#4A7C8E	Buttons, links, user bubbles
Secondary	#7FB5A0	Accents, success states
Accent	#E8956D	Warnings, speaking state
Background	#F7F5F2	App background
Surface	#FFFFFF	Cards, nav bar
Text Primary	#1E2D3D	Body and headings

Accessibility features:

• Minimum 44×44pt tap targets throughout
• accessibilityLabel and accessibilityRole on all interactive elements
• Configurable text size (small / medium / large)
• High contrast mode toggle
• Subtitle and audio toggles for avatar responses
• Haptic feedback toggle

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Disclaimer

DementiaGuide AI provides information for general guidance only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider for dementia-related concerns.

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License

Private — all rights reserved.