These days, collaboration needs to happen in real time. Whether you’re taking group notes in a meeting, live-blogging an event, or just collecting lunch orders in a hurry, SubEthaEdit can help. This powerful text and code editor allows multiple people—30 or more without breaking a sweat—to contribute to and edit a document simultaneously.

When someone edits a shared SubEthaEdit document, their changes appear instantly on fellow users’ screens, helpfully color-coded by collaborator so it’s easy to see who typed what. Deep levels of undo allow a walk-back through each change. And if you save your work in SubEthaEdit’s file format (rather than as a standard text file), you can review every edit and who made it even after you’ve closed the document.

Unlike cloud-based services, no internet connection is required to collaborate with SubEthaEdit. Just open a document and advertise it over your local network; others can join right from within the app. (SubEthaEdit also lets you share a document over the web, though this requires a network gateway that allows automatic port mapping and a publicly reachable IP address.)

In addition to its robust collaboration tools, SubEthaEdit is a great text editor. It offers syntax highlighting with support for over two dozen languages and formats (including Markdown, HTML, JavaScript, Objective-C, Swift, and JSON), and its built-in web preview displays, in real time, the results of any edits you make to HTML. Serious coders will appreciate features like code/bracket auto-complete, grep, and code folding.

Using SubEthaEdit is like having everyone on your team connect their keyboards to the same Mac. But the app also provides enough structure to make mass collaboration a breeze.