AI Chat Assistant App (ChatGPT API) – React Native Expo Source Code

Description

Launch your own ChatGPT-style assistant. Nova AI is a complete chat app with streaming responses, multiple conversations stored on the device, ready prompt presets and a full settings screen. It talks to OpenAI or any OpenAI-compatible endpoint (OpenRouter, Groq, Together, local LM Studio or Ollama) and has a built-in demo mode so it works right after install.

Features

• Chats list with auto titles, last message preview and delete
• Chat screen with streaming answers (SSE), Stop and Regenerate, copy message, suggestion chips for new chats
• Markdown style rendering with code blocks
• Prompt library: 9 presets in categories Write, Learn, Work and Fun (email writer, idea generator, translator and more)
• Settings: API key (hidden with show toggle), base URL, model, system prompt, temperature, streaming on or off
• Demo mode with sample answers when no API key is set
• Light, dark or system theme, delete all chats, About screen
• Conversations stored on the device with AsyncStorage
• Runs on Android, iOS and Web

Tech stack

• React Native 0.74, Expo SDK 51
• TypeScript (strict)
• React Navigation 6: bottom tabs and native stack
• OpenAI-compatible Chat Completions API with streaming (XMLHttpRequest + SSE parser)
• @react-native-async-storage/async-storage, expo-clipboard
• Jest tests for the SSE parser, API client and chat storage

Requirements

• Node.js 18 or 20
• Expo Go on your phone, or Android emulator / iOS simulator
• Optional: EAS CLI for store builds
• An API key from OpenAI or another OpenAI-compatible provider (optional, demo mode works without it)

How to install and run

1. Unzip the archive and open the project folder
2. Run npm install
3. Run npx expo start and scan the QR code with Expo Go (or press a / i / w)
4. Open Settings, paste your API key and choose a model
5. Run tests with npm test, build for stores with eas build

How to rebrand

• App and assistant name: app.json and APP_NAME, ASSISTANT_NAME in src/config.ts
• Colors: BRAND_PRIMARY, BRAND_ACCENT in src/config.ts and palettes in src/theme/theme.ts
• AI defaults: base URL, model, temperature, system prompt in src/config.ts
• Prompt presets: src/data/presets.ts
• Icon and splash: replace files in assets/
• Package id: app.json (current: com.appforge.novaai)

What’s included

• Full TypeScript source code (App.tsx, src, assets, app.json, package.json, package-lock.json)
• Jest tests
• README.md with setup, rebranding and project structure
• LICENSE file
• Screenshots folder

Screenshots

License

Commercial license: use the source code in one end product (one app) for yourself or one client, free or paid. Reselling or redistributing the source code as a template is not allowed. Full text in the LICENSE file.