Pick your note system first. The AI is the easy part, and it is all converging anyway. Notion AI, Mem, and Obsidian differ in the AI features around the edges. They differ enormously in where your notes live. That is the decision.
Notion AI wins if your notes are already in Notion. Summaries, drafts, questions across the workspace, all seamless because it is one product. Mem's pitch is automatic organization: it files things for you, which is catnip if your notes are a beautiful mess. Obsidian's AI is plugin-based and local-first, for people who want their notes to outlive any company. The tradeoff nobody leads with: lock-in versus longevity. Notion and Mem are cloud products. If they change pricing or shut down, your system shakes. Obsidian's files are plain text on your disk, yours forever, but you assemble the AI yourself.
Choose the system you would use without AI, then bolt the AI on. That is the whole AI tool migration guide lesson for notes: your notes are the hardest thing you own to move, so pick for the decades, not the demo. Run an AI tool alternatives comparison on the system, not the feature list. The best note app is usually the one you are already in, plus AI.
Match to the job, as always. Students and researchers: Obsidian's local files and citation plugins are hard to beat. Teams sharing a knowledge base: Notion's collaboration wins.
I run 210 head-to-head AI tool comparisons at aitoolguide.fyi with clear verdicts. Building a productivity tool? Sponsored placements reach buyers choosing right now.