Free open source alternative app list of AI Chat :

AnythingLLM

Key features Chat with your own documents using retrieval-augmented generation (RAG) and any supported LLM Desktop application with a single, unified interface for chatting, embedding, and managing vector storage Full support for local models, enabling fully offline and private use Works with a wide range of LLM providers, letting you swap models without changing your workflow Open source under the MIT license, giving you transparency and control over your data Platforms: Windows, macOS, Linux Links Official website Source code Pricing Fully free and open source under the MIT license, with optional paid cloud hosting tiers.

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Open WebUI

Key features Self-hosted AI chat interface that you can run on your own hardware, keeping conversations and data under your control. Works with both local models (for example via Ollama) and remote LLM providers from a single web UI. Extensible, community-driven project designed to be customized and adapted to different workflows. Multi-model support, letting you switch between different language models without leaving the app. Browser-based chat experience that requires no client installation beyond a modern web browser. Platforms: Windows, macOS, Linux. Links Official website Source code Pricing: Fully free and open source under the MIT license; self-hostable Docker image with no paid tier.

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LibreChat

Key features Unifies multiple AI models — including OpenAI, Anthropic, and others — into a single conversation platform. Supports plugins to extend functionality. Enables sharing conversations and configurations. Self-hosted deployment for full control over your data and setup. Platforms: Windows, macOS, Linux Links Official website Source code repository Pricing Free. Fully free and open-source under the MIT license; self-host your own instance with no usage limits.

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LobeChat

Key features Open-source, modern AI chat interface for managing, building, and running AI agent teams. Works across multiple LLM providers, letting you switch or combine models in one place. Supports self-hosting for full control over your data and deployment. Extensible via plugins to add custom tools and capabilities. Rich feature set covering chat organization, agent management, and team workflows. Platforms: Windows, macOS, Linux Links Official website: https://lobehub.com/ Source code: https://github.com/lobehub/lobe-chat Pricing Free and fully open-source under Apache-2.0. You can self-host it or use the public demo.

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GPT4All

Key features Run local large language models directly on your own device, enabling fully private and offline AI chat without relying on cloud services. Keep all conversations and data on your hardware — nothing is uploaded, protecting your privacy. Free and open-source desktop application released under the permissive MIT license. No usage limits; all models execute locally on your own hardware. Cross-platform desktop support for Windows, macOS, and Linux. Platforms: Windows, macOS, Linux Links Official website: https://gpt4all.io Source code repository: https://github.com/nomic-ai/gpt4all Pricing Free. GPT4All is completely free and open-source (MIT) with no usage limits; all models run locally on your hardware. It serves as a private, offline alternative to cloud-based AI chat tools such as ChatGPT.

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Botpress

Key features Open-source platform for building AI agents and chatbots powered by large language models. Drag-and-drop flow design for creating conversational workflows without heavy coding. Full source code available for customization and self-hosting. Runs on Windows, macOS, and Linux. Platforms: Windows, macOS, Linux. Links: Official website · Source code Pricing: Freemium. The self-hosted open-source version is available under the MIT license and includes all core features.

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5ire

Key features Cross-platform desktop AI assistant compatible with local and cloud-based large language models Built-in knowledge base support for grounded, context-aware responses Designed for offline, private AI usage on personal devices Available as a free open-source application under the MIT license Platforms: Windows, macOS, Linux Links Official website Source code Pricing: Free open-source desktop app released under the MIT license.

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Cherry Studio

Key features Multi-model AI desktop client supporting many LLM providers from a single interface Local-first, privacy-focused design for handling AI conversations Ability to chat with and compare models side by side Open-source codebase released under the AGPL-3.0 license Cross-platform desktop application for Windows, macOS, and Linux Platforms: Windows, macOS, Linux Links Official Website Source Code Pricing: Fully free and open source under the AGPL-3.0 license.

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Fullmoon

Key features Native macOS and iOS application built specifically for Apple platforms. Chat interface designed for interacting with large language models. Runs conversations locally on-device, keeping data private. Focused on privacy by avoiding cloud-based processing. Tailored experience on both Mac and iPhone/iPad. Platforms: macOS, iOS Links Official website Pricing: Free to download; closed-source proprietary app.

FreemacOSiOS

CopilotKit

CopilotKit is a free, open-source alternative to CommandBar . CopilotKit Docs · Examples · Enterprise Intelligence Platform · Discord Build agent-native applications — on any framework, on any surface. Generative UI, shared state, and human-in-the-loop workflows for React, Angular, Vue, React Native — and in Slack and Microsoft Teams. What is CopilotKit CopilotKit is a best-in-class SDK for building full-stack agentic applications, Generative UI, and chat applications. What started as a React library is now the horizontal layer between your agents and your users : the same agent can power your web app, your mobile app, and your team's Slack or Microsoft Teams workspace. We are the company behind the AG-UI Protocol - adopted by Google, LangChain, AWS, Microsoft, Mastra, PydanticAI, and more! Quick Start Up and running in under five minutes. All you need is an LLM key (OpenAI, Anthropic, Gemini, etc.). npx copilotkit@latest create Agent Skills CopilotKit ships agent skills that teach your coding agent (Claude Code, Codex, Cursor, Gemini, and others) how to set up, build with, integrate, debug, and upgrade CopilotKit. Install them into any project directory: npx copilotkit@latest skills install Run it again any time to refresh to the latest skills. Bring Your App to Life Whole.Generative.UI.v5.mp4 Add AI to your app in 1 minute Features: Chat UI – A fully customizable chat interface that supports message streaming, tool calls, and agent responses. Backend Tool Rendering – Enables agents to call backend tools that return UI components rendered directly in the client. Generative UI – Allows agents to generate and update UI components dynamically at runtime based on user intent and agent state. Shared State – A synchronized state layer that both agents and UI components can read from and write to in real time. Human-in-the-Loop – Lets agents pause execution to request user input, confirmation, or edits before continuing. Self-Learning (early access) – Agents that continuously improve from user feedback via in-context reinforcement learning (CLHF). 🧩 Works With Your Stack One agent backend. Every frontend. Platform Status Get Started ⚛️ React / Next.js ✅ GA Quickstart 🅰️ Angular ✅ Supported Source Code & Quickstart 💚 Vue ✅ Supported Source Code - Quickstart coming soon 📱 React Native ✅ Supported Quickstart 💬 Slack / Microsoft Teams ✅ Supported Channels · Quickstart 🔜 Discord / WhatsApp / Telegram / Google Chat / iMessage / SMS 🟡 Coming soon Channels Your agent logic stays the same — AG-UI handles the wire protocol, CopilotKit handles the UI layer for each framework and channel. 💬 Channels: One Agent, Every Chat App The Channels SDK takes the agent you already built and drops it into the chat apps your users live in — same tools, same shared state, same human-in-the-loop, no rewrite ( Learn more ). Slack – Agents as first-class Slack apps: threads, tool calls, and human-in-the-loop approvals right in the channel. Microsoft Teams – Bring agentic workflows to the enterprise, where your org already lives. 👉 Explore Channels → 🧠 Self-Learning Agents Improve your product by learning over time. With Continuous Learning from Human Feedback (CLHF) , part of the CopilotKit Intelligence Platform , agents improve with every interaction: In-context reinforcement learning – Agents automatically improve from user interactions, no model fine-tuning required. Automatic prompt augmentation – Agent behavior adapts based on recent interactions and outcomes. Per-user adaptation – Agents learn individual preferences and get better for each user over time. Threads & persistence – Full interaction history — generative UI, human-in-the-loop, shared state — captured across sessions. Available via CopilotKit Cloud or self-hosted. 🔒 Early access: We're onboarding teams now. 👉 Request early access → cpk-cli.mp4 What this gives you: CopilotKit installed – Core packages are fully set up in your app Provider configured – Context, state, and hooks ready to use Agent <> UI connected – Agents can stream actions and render UI immediately Deployment-ready – Your app is ready to deploy Complete getting started guide → How it works: CopilotKit connects your UI, agents, and tools into a single interaction loop. This enables: Agents that ask users for input Tools that render UI Stateful workflows across steps and sessions One agent, deployed across web, mobile, and chat platforms ⭐️ useAgent Hook The useAgent hook sits directly on AG-UI, giving you full programmatic control over the agent connection. // Programmatically access and control your agents const { agent } = useAgent ( { agentId : "my_agent" } ) ; // Render and update your agent's state return < div > < h1 > { agent . state . city } < / h1 > < button onClick = { ( ) => agent . setState ( { city : "NYC" } ) } > Set City < / b u t t o n > < / div > Check out the useAgent docs to learn more. CopilotKit.UseAgent.Graphic.Motion_2.mp4 Generative UI Generative UI is a core CopilotKit pattern that allows agents to dynamically render UI as part of their workflow. demo-generative-ui.mp4 Compare the Three Types Explore: Static (AG-UI Protocol) Declarative (A2UI) Open-Ended (MCP Apps & Open JSON) Generative UI educational repo → 🖥️ AG-UI: The Agent–User Interaction Protocol Connect agent workflows to user-facing apps, with deep partnerships and 1st-party integrations across the agentic stack—including LangChain, CrewAI, Mastra, PydanticAI, and more. npx create-ag-ui-app my-agent-app Learn more in the AG-UI README → 🤝 Community What's New Have questions or need help? Join our Discord → Read the Docs → Try the Enterprise Intelligence Platform → Stay up to date with our latest releases! Follow us on LinkedIn → Follow us on X → 🙋🏽‍♂️ Contributing Thanks for your interest in contributing to CopilotKit! 💜 We value all contributions, whether it's through code, documentation, creating demo apps, or just spreading the word. Here are a few useful resources to help you get started: For code contributions, CONTRIBUTING.md . For documentation-related contributions, check out the documentation contributions guide . Want to contribute but not sure how? Join our Discord and we'll help you out! 📄 License This repository's source code is available under the MIT License .

FreeAndroidiOS

Zola

Key features AI chat companion designed for conversational interactions Versatile model support, allowing users to work with different AI backends Cross-platform desktop client for Windows, macOS, and Linux Tagged as an AI chat and multi-model tool Marked for AI review, indicating it is listed pending further evaluation Platforms: Windows, macOS, Linux Links: Pricing: Free

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jan

jan is a free, open-source alternative to ChatGPT . Jan is an open-source AI assistant that runs fully offline on your computer, providing a ChatGPT alternative with local language models.

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