ProtoText is a free, offline-first desktop app that helps with brainstorming, note-taking, multilingual text composition, flexible presentations, knowledge network building, and project content management. It uses a card-based approach and one-key markup to offer flexible control over content. It also features built-in AI assistance with ChatGPT for generating content and offers the ability to translate content into multiple languages while retaining the original markup. ProtoText also allows for full-screen presentation mode and data export with semantic formatting. It prioritizes minimalism, privacy, and security with strong encryption. It is open-source and available for Mac and Windows.