AICat is an open-source multiplatform client for ChatGPT built with SwiftUI, running on iOS, iPadOS, and macOS. Published on GitHub with about 290 stars and last updated in July 2025, it recreates the ChatGPT web app experience as a native Apple application.
AICat covers the familiar chat workflow natively: create chats from prompts, manage conversations and messages with full create, read, update, and delete support, and copy code blocks cleanly. A command mode inspired by Telegram speeds up common actions, and custom request parameters can be set for every conversation. Chats can start a fresh session when the context grows, messages can be shared as images or exported as Markdown, and data syncs through iCloud. People with an OpenAI account can enter their own API key and even a custom API host in developer mode, while people without a key can subscribe to a monthly premium inside the app to access the features. The repository also serves as a from-scratch example of building a cross-platform Apple app with networking, database storage, and in-app purchases.
The app is also distributed through TestFlight and the App Store, and the project maintains a Telegram channel for release news. For learners, the repository doubles as a compact case study in SwiftUI app architecture, showing how networking requests, local database storage, and in-app purchases fit together inside a single cross-platform codebase that targets phones, tablets, and desktops at once.
The AICat source code is free and open on GitHub. The distributed app can be used with your own OpenAI API key, and an optional monthly premium subscription unlocks access for users without a key.
AICat is for Apple users who want a fast native ChatGPT client with prompt management and export options, and for Swift developers studying a complete SwiftUI app.