Logseq

Logseq is a free and open-source, personal knowledge base and note-taking application which can store data locally. It supports both Markdown and org-mode syntax.

History

Tienson Qin started Logseq as a platform to store interconnected information on infinite graphs which would run on any device.
Logseq Inc was formed with An Vu, Huang Peng, Tienson Qin, and ZhiYuan Chen as founders, which raised over $4.1M for the growth. This seed funding round included investments from Stripe CEO Patrick Collison, Shopify CEO Tobias Lütke, and ex-GitHub CEO Nat Friedman.

Logseq can make semantic connections between notes, tasks, to-do lists, flashcards or PDF markups.
Logseq can help track and manage sources for research using Zotero integration.Look and feel of the app can be customized using themes. Live query builder helps to create queries using point and click.
Logseq is available for Windows, Linux, macOS, BSD, Android and iOS.

Graph view shows visually how the notes or different information is interconnected.

Whiteboard helps to create and edit diagrams on logseq.

Flashcards help to learn or memorize information by reviewing cards.

Plugins helps to add features which are not on the base app including integrations to other tools and platforms.