Yack is a MacOS app that allows users to access ChatGPT, an AI language chatbot developed by OpenAI, directly from their menu bar. It requires an Open AI key for usage.

The app is lightweight, fast, and simple, built with Rust and weighing in at less than 10 MB. Yack offers a keyboard-first design, multiple themes, and markdown support, with bullets, numbered lists, code blocks, and tables.

Additionally, Yack is designed to be a private tool that doesn't store any user data in its servers. Instead, anything that needs to be stored is kept on the user's device and never leaves it.

In addition to the current features, Yack has promised several upcoming features, including cross-app integration and searchability. Users will be able to pick context from other apps and use their own prompts with Yack, and search through their chats.

Furthermore, Yack is compatible with both the Apple Silicon and Intel chips for MacOS version 2020 and later for the former, and earlier versions for the latter.

Overall, Yack offers a seamless and convenient experience for MacOS users to utilize OpenAI's ChatGPT without having to go through a browser.