Tumblr’s Mac app has two features. It lets you browse just Tumblr, and it lets you post content straight to Tumblr.
The first feature means you can browse Tumblr in full screen. As the Yahoo-owned company puts it, the point is “that your computer displays 0 percent non-Tumblr content.”
Why would anyone want to do that? In its announcement, Tumblr explains the rather obvious: “The rest of the Internet? Don’t worry about it. You’re not missing anything.”
As for the second feature, it lets you post to Tumblr from almost anywhere on your Mac via the share button that was first introduced with Mountain Lion. If a window has a share button, you can share its contents to Tumblr.
In typical Tumblr fashion, the company naturally had to show off how the app works using a GIF:
Most content posted to Tumblr comes from mobile. That’s unlikely to change, but it can’t hurt to encourage more desktop content and usage as well.