Apps to Annotate screenshots

Gruik is a powerful, free, and open-source note-taking service designed for users who value privacy, organization, and control over their data. Offering robust features like hierarchical organization, offline access, rich text formatting, and synchronization options, it provides a flexible platform for managing notes, ideas, and personal knowledge wikis.

ShareX is a free and open-source utility for capturing and sharing screenshots, screen recordings, and various other forms of content. It offers a wide array of tools for image manipulation, file uploads, and automation, making it an incredibly versatile application.

Shutter is a comprehensive screenshot utility specifically designed for Linux systems. It offers robust features for capturing, editing, and sharing screenshots, making it a versatile tool for developers, designers, and everyday users.

Greenshot is a free and open-source screenshot utility for Microsoft Windows. It allows users to capture full or partial screenshots, annotate them with various tools, and easily share or save the images.