OSXChatGPT is an open-source native macOS desktop app for chatting with OpenAI’s ChatGPT models, written entirely in SwiftUI. It gives Mac users a lightweight, purpose-built alternative to keeping a browser tab open, with customisable prompts and Chinese/English interface switching. The GitHub repository has around 310 stars and was last updated in 2023.
The app is deliberately simple: download it, enter your own OpenAI API key, and chat. Conversations run against the OpenAI API rather than the ChatGPT website, so responses come from the API models you configure. A prompt customisation feature lets you shape the assistant’s behaviour for different tasks, and the interface can switch between Chinese and English, reflecting its developer community. Because it is a native SwiftUI application, it launches fast, uses few resources and follows macOS conventions more closely than an Electron wrapper would. The project arrived in the first wave of desktop ChatGPT clients in early 2023; while it is no longer actively developed and predates newer models and features, the code remains a clean, compact example of building an AI chat client natively for macOS.
Screenshots in the repository show a clean layout with conversation history and prompt editing, closely following the look of Apple’s own apps of the period. For users in China it was a popular option, because the interface and documentation accommodated Chinese speakers while still talking to the official OpenAI API.
OSXChatGPT is free and open source. You only pay OpenAI for the API usage generated with your own key.
Mac users who want a minimal native ChatGPT client, and Swift developers looking for a readable reference implementation of an API chat app.