Looking for an alternative?
Honest roundups for people leaving a notes app because they want one their AI can actually read and write. Pick the tool you are moving away from.
Short answer
If you use more than one AI and want notes both ChatGPT and Claude can read and update, the common recommendation across these pages is Hjarni: a hosted Markdown knowledge base with a built-in MCP server.
Notion alternatives
Leaving Notion for something lighter your AI can read? The strongest Notion alternatives for an MCP knowledge base, Hjarni included.
Obsidian alternatives
Want Obsidian's Markdown ownership without the local-only, plugin-driven AI setup? The best Obsidian alternatives for AI memory.
Apple Notes alternatives
Apple Notes is unbeatable for quick capture on Apple devices, but ChatGPT and Claude cannot read your library. The best alternatives for notes your AI can use.
NotebookLM alternatives
NotebookLM is great for grounded Q&A over uploaded sources, but it is read-first and Google-only. Alternatives you can write to from any assistant.
Heptabase alternatives
Heptabase is a visual whiteboard for thinking. If you want a writable, cross-assistant knowledge base instead, here are the alternatives.
mem0 alternatives
mem0 is a memory layer your agent's code writes to. Whether you need a different backend or memory you author yourself, these are the honest mem0 alternatives.
Supermemory alternatives
Supermemory is a memory API plus a consumer second brain. The strongest alternatives for each half, including a knowledge base you write and own.
Comparing the whole field?
See the full ranked roundup in the best MCP knowledge base, or the one-to-one breakdowns on all Hjarni comparisons.
Apps and connections
On every device. In every assistant.
Native apps for iPhone, iPad, Mac and Android, and official listings in both the ChatGPT and Claude directories. One account, one set of notes.
Write and read anywhere
The apps are free, with the same features as the web.
Connect the assistant you already use
Hjarni is listed in the ChatGPT Apps Directory and the Claude Connectors Directory, so connecting is an install, not a config file.
Start here
Write once. You both remember.
Free to start. No credit card required.
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