DEVONthink 4 vs Obsidian
Both are bought outright, both sit in writing, and both are bought by people leaving Notion, Evernote. Here is what actually differs — including what each price does not buy.
The short answer
- Obsidian is free; DEVONthink 4 costs $99.
- Obsidian has the cleaner licence: free, against own it, pay for major upgrades for DEVONthink 4.
Side by side
 DEVONthink 4$99Paid upgrades |  ObsidianFreeFree | |
|---|---|---|
| What it is | research database for documents, mail and scans that stays yours | local-first markdown vault, free with no feature gates |
| Price | $99 | Free |
| Licence | Own it, pay for major upgrades | Free |
| What you get | One payment, and the developer charges for major versions on a stated cadence. | No licence to buy. |
| The catch | Updates stop after a year unless you pay to extend; the version you have keeps working forever | Multi-device sync is $48 a year unless you wire up iCloud or git yourself |
| Macs per licence | 2 | not established |
| Account required | no | optional |
| Works offline | yes | yes |
| Apple Silicon | Yes | Yes |
| Free trial | Yes | No |
| On Setapp | No | No |
| Minimum macOS | not established | not established |
| App Store rating | not established | not established |
| Last updated | not established | not established |
| Price checked | 2026-09-22 | 2026-09-22 |
Apple’s public API reports a rating for only a small minority of Mac apps, and returns zero for most of the rest even when the store page plainly shows reviews. A blank here means we could not read a number, never that an app is unrated or disliked.
In their own right
DEVONthink 4
A full-text-searchable database for PDFs, scans, web archives, email and notes, with OCR and related-document suggestions. One payment, two Macs, and a licence that is never deactivated.
Obsidian
A markdown editor over a folder of plain files on your own disk, with backlinks, a graph view, Canvas and a very large plugin ecosystem. Free for any use, personal or commercial, with no account required.