Simplifying, Textpack is a markdown file, plus optional image files, packed into single zip file.
In Keepmark you can configure other external tools to work with. Mainly, I can be other applications, or shell scripts run for the selected document. Before you start you should configure them in Application Settings.
Keepmark can store any files that are on your computer. Moreover, it previews many popular document formats, allowing you to view them without having to open them in a dedicated application.
Keepmark has support for spell checking when creating notes. To enable this functionality, you must first go to the app's settings and download the dictionaries of your choice.
Tags are one of the basic tools for organizing documents. When working with tags in Keepmark, you can start by defining a list of tags for a given workspace, or simply create them by assigning to documents right away. All tags assigned to documents will be visible in the application's side-bar, allowing you to quickly filter the list of documents to selected subjects.
In Keepmark you can add relations for an existing document, to other documents, tasks, or people. This can be done through the side panel of an open document.
You will find a short guide how to configure workspace synchronization in the attached video.
See attached video to see how to use Tasks Module in Keepmak.
Work context is special view where you can preview your main document you working on, and at the same time browse other documents in workspace, or browse content in the web. It is specially useful when you making some research or working on your notes and you want to have convenient access to your other resources.
You will find a short guide how to get started with Keepmark in the attached video.