The second feature release for DEVONthink 4 — DEVONthink 4.2 Cassini — introduces a refreshed look with a new app icon and full support for Apple’s Liquid Glass design on macOS Tahoe. On macOS Sequoia and later, sidebars and inspectors now animate smoothly in and out, and the Navigate sidebar is spring-loaded. Simply drag items to the window edge to reveal it automatically. PDF documents on macOS Tahoe also respect your dark mode preference for more comfortable reading.
The chat assistant gains powerful new capabilities: adjust many options directly within the chat window, and access up to 50 saved conversations to pick up right where you left off. You can now choose between DEVONthink, Perplexity, or Exa for web and Wikipedia searches, giving you control over speed versus freshness. Updated AI models including Claude 4.5, GPT 5.2, Gemini 3, and Google Nano Banana Pro, deliver improved performance across all AI use. When generating images, you can choose the aspect ratio.
New workflow tools help you work faster: the detachable Graph popover lets you visualize document connections, you can manually save named versions for finer revision control, and annotation documents are now easier to create, locate, and open directly from menus and inspectors. Markdown documents also support smart quotes and dashes for polished typography.
For users of the legacy generation of DEVONthink, we’ve released version 3.9.17 with quality-of-life improvements and bug fixes.
You can find a complete list of all improvements by choosing Help > Release Notes inside the application. We recommend this update to all users of DEVONthink for Mac. Get it by using the application’s update function or from our Download page. The New & Improved page also highlights what’s new in each feature release.
We name this release after the Cassini lunar crater and its namesake, Giovanni Domenico Cassini (1625–1712). The Italian-French astronomer served as the first director of the Paris Observatory. Cassini was a methodical observer and organizer of knowledge, systematically cataloging celestial phenomena and discovering four of Saturn’s moons and the division in its rings. His dedication to precise observation and documentation lives on as one of the foundational principles of science.
I’m thrilled with the restraint chosen in rolling out Liquid Glass. It really looks good.
Version 4.2 does not extend the sidebars into the toolbar area and it doesn’t make the sidebars translucent, allowing content to bleed into them. Another app I depend on, OmniOutliner, has not shown that restraint. Their latest version is unusable for me.
I also came to congratulate DEVONthink Team in keeping the app super usable and making the best out of the Liquid Glass design. Compared to so many other apps, and OS itself, I feel like DT 4.2 actually became better as a result of re-design!
The support assistant is loaded online so we’ll adjust this in the next few days. We also need to update the DEVONthink icon on the website. Small company
I fully agree. This is so much better than Apple’s own implementation in apps like Safari, where showing and hiding the Sidebar makes the toolbar icons jump around in a janky way.
Like with DtTG 4, DEVONtechnologies did a great job in my opinion to use Liquid Glass to make a complex application look andfeel a bit more approachable, joyful, and “modern”, without impacting functionality and without violating tried and tested concepts of how a Mac app should work.
I think one can definitely have varying opinions on the general appearance of Liquid Glass, for example in toolbars (where I like in general that buttons have an outline again, although the lack of contrast between the floating buttons and the background is questionable), but the more important problem in lots of Mac apps, including Apple’s own, is that the Liquid Glass elements just don’t feel particularly great and fluid to use, which defeats the purpose altogether. DEVONthink feels great.
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