Logseq
Logseq is the closest thing to Obsidian that takes a fundamentally different approach. Where Obsidian is file-first, Logseq is block-first — every bullet point is an addressable unit you can reference, embed, or query from anywhere in your graph.
The daily journal workflow is where Logseq really shines. Open the app, start typing, and everything lands in today's page. Over time, tags and page references build an organic knowledge graph without any upfront organization. For people who found Obsidian's "blank canvas" problem overwhelming, this is a revelation.
The plugin ecosystem is smaller than Obsidian's (~200 vs 1,500+), but the core feature set is more complete out of the box. PDF annotation, flashcards, and a Whiteboard view are all built in.
Pros
- Fully open-source (AGPL-3.0)
- Block-level referencing and queries
- Built-in flashcards (spaced repetition)
- Works entirely offline with local files
Cons
- Performance degrades with very large graphs (10k+ pages)
- Mobile apps are functional but laggy
- Markdown export isn't always clean