Kai

# Kai

<img src="https://img.shields.io/badge/Platform-Web-f7df1c?logo=javascript" alt="Web"> <img src="https://img.shields.io/badge/Platform-Android-34a853.svg?logo=android" alt="Android" /> <img src="https://img.shields.io/badge/Platform-iOS-lightgrey.svg?logo=apple" alt="iOS" /> <img src="https://img.shields.io/badge/Platform-Windows/macOS/Linux-e10707.svg?logo=openjdk" alt="Platform JVM" />
<div align="center">
<img src="kai-mascot.png" height="80">

An **open-source AI assistant with persistent memory** that runs on **Android, iOS, Windows, Mac, Linux, and Web**.

**[Documentation](https://simonschubert.github.io/Kai/docs/)**
</div>

## Installation

[![App Store](https://raw.githubusercontent.com/SimonSchubert/Kai/main/screenshots/app_store_badge.png)](https://apps.apple.com/us/app/kai-ai/id6758148023)
[![Play Store](https://raw.githubusercontent.com/SimonSchubert/Kai/main/screenshots/play_store_badge.png)](https://play.google.com/store/apps/details?id=com.inspiredandroid.kai)
[![F-Droid](https://raw.githubusercontent.com/SimonSchubert/Kai/main/screenshots/fdroid_badge.png)](https://f-droid.org/en/packages/com.inspiredandroid.kai/)
[![Web](https://raw.githubusercontent.com/SimonSchubert/Kai/main/screenshots/web_badge.png)](https://simonschubert.github.io/Kai)

Homebrew (macOS):

```
brew install --cask simonschubert/tap/kai
```

AUR (Arch Linux):

```
yay -S kai-bin
```

Winget (Windows):

```
winget install SimonSchubert.Kai
```

### Direct Downloads

| Platform | Format | Download |
|----------|--------|----------|
| Android | APK | [GitHub Releases](https://github.com/SimonSchubert/Kai/releases) |
| macOS | DMG | [GitHub Releases](https://github.com/SimonSchubert/Kai/releases) |
| Windows | MSI | [GitHub Releases](https://github.com/SimonSchubert/Kai/releases) |
| Linux | DEB | [GitHub Releases](https://github.com/SimonSchubert/Kai/releases) |
| Linux | RPM | [GitHub Releases](https://github.com/SimonSchubert/Kai/releases) |
| Linux | AppImage | [GitHub Releases](https://github.com/SimonSchubert/Kai/releases) |

## Features

- **Persistent memory** — Kai remembers important details across conversations and uses them automatically
- **Customizable soul** — Define the AI's personality and behavior with an editable system prompt
- **Multi-service fallback** — 17 LLM providers with automatic failover
- **Tool execution** — Web search, notifications, calendar events, shell commands, and more
- **MCP server support** — Connect to remote tool servers via the Model Context Protocol
- **Autonomous heartbeat** — Periodic self-checks that surface anything needing attention
- **Settings export/import** — Backup and restore all settings as a JSON file
- **Encrypted storage** — Conversations stored locally with encryption
- **Text to speech** — Listen to AI responses
- **Linux Sandbox** — On Android, the AI can run shell commands, scripts, and tools in a secure sandboxed Linux environment
- **Image attachments** — Attach images to any conversation

## Linux Sandbox (Android)

On Android, Kai includes a built-in Linux environment that the AI can use to execute shell commands, run scripts, and operate tools on your behalf. This turns Kai from a chat-only assistant into one that can take real action — installing packages, processing data, running Python scripts, and more.

- **Powered by Alpine Linux** — A lightweight ~3 MB download sets up a full Linux userland via [proot](https://proot-me.github.io/), no root required
- **Optional packages** — One tap installs bash, curl, wget, git, jq, python3, pip, and Node.js
- **Interactive terminal** — A built-in terminal lets you run commands manually alongside the AI
- **Secure** — Everything runs sandboxed inside the app with no access to the host system

Enable it in **Settings > Linux Sandbox**.

<img src="screenshots/mobile-7.png" alt="Linux Sandbox" height="300">

## Screenshots

### Desktop

<img src="screenshots/desktop-1.png" alt="Desktop App" height="300">

### Web

<img src="screenshots/web-1.png" alt="Web App" height="300">

### Mobile

<img src="screenshots/mobile-1.png" alt="Mobile Screenshot 1" height="300"> <img src="screenshots/mobile-2.png" alt="Mobile Screenshot 2" height="300"> <img src="screenshots/mobile-3.png" alt="Mobile Screenshot 3" height="300"> <img src="screenshots/mobile-4.png" alt="Mobile Screenshot 4" height="300"> <img src="screenshots/mobile-5.png" alt="Mobile Screenshot 5" height="300"> <img src="screenshots/mobile-6.png" alt="Mobile Screenshot 6" height="300">

## How It Works

```
                        ┌────────┐
                        │  User  │
                        └───┬────┘
                            │ message
                            ▼
               ┌─────────────────────────┐
               │          Chat           │
               │                         │
               │  prompt + memories      │
               │        │                │
               │        ▼                │
               │    ┌────────┐           │
               │    │   AI   │◀─┐        │
               │    └───┬────┘  │        │
               │        │   tool calls   │
               │        │   & results    │
               │        ▼      │        │
               │    ┌────────┐ │        │
               │    │ Tools  │─┘        │
               │    └───┬────┘          │
               │        │               │
               └────────┼───────────────┘
                        │ store / recall
                        ▼
               ┌─────────────────┐    hitCount >= 5
               │     Memory      │───────────────────┐
               │                 │                   │
               │  facts, prefs,  │                   ▼
               │  learnings      │          ┌────────────────┐
               │                 │◀─delete──│ Promote into   │
               └─────────────────┘          │ System Prompt  │
                        ▲                   └────────────────┘
                        │ reviews
                        │
               ┌─────────────────┐
               │    Heartbeat    │
               │                 │
               │  autonomous     │
               │  self-check     │
               │  every 30 min   │
               │  (8am–10pm)     │
               │                 │
               │  all good?      │
               │  → stays silent │
               │  needs action?  │
               │  → notifies user│
               └─────────────────┘
```

- **Chat** — User sends a message. The AI responds, calling tools (memory, web search, shell, etc.) in a loop until it has a final answer.
- **Memory** — The AI stores and recalls facts, preferences, and learnings. Memories that prove useful (5+ hits) can be promoted into the system prompt permanently.
- **Heartbeat** — A background self-check runs every 30 minutes. It reviews memories, pending tasks, and emails. If something needs attention, it notifies the user. Otherwise, it stays silent.

## Supported Services

| Service | Website |
|---|---|
| Anthropic | https://console.anthropic.com |
| Cerebras | https://cerebras.ai |
| DeepSeek | https://www.deepseek.com |
| Gemini | https://aistudio.google.com |
| Groq | https://groq.com |
| Hugging Face | https://huggingface.co |
| LongCat | https://longcat.chat |
| Mistral | https://mistral.ai |
| Moonshot AI | https://moonshot.cn |
| NVIDIA | https://developer.nvidia.com |
| Ollama Cloud | https://ollama.com |
| OpenAI | https://openai.com |
| OpenRouter | https://openrouter.ai |
| Together AI | https://together.ai |
| Venice AI | https://venice.ai |
| xAI | https://x.ai |
| OpenAI-Compatible API | Ollama, LM Studio, etc. |

Plus a built-in **Free** tier that requires no API key.

## MCP Servers

Kai supports the [Model Context Protocol](https://modelcontextprotocol.io/) for connecting to external tool servers. Go to **Settings > Tools > Add MCP Server** to connect to any Streamable HTTP MCP endpoint, or pick from a curated list of popular 

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