On July 30, Apple seeded the very first beta of Mac OS X Mavericks 10.9.5 to developers. Since then, Apple’s been working diligently to keep a timely refresh for its betas to developers.
On August 19, Apple officially seeded the fourth beta of OS X Mavericks 10.9.5, build 13F18, to developers. With this newest batch, it’s been less than a week since Apple released the third beta, but more than ten days since the second beta landed. It’s been more than a month since Apple officially released OS X Mavericks 10.9.4 to the public.
It is still unclear what, exactly, Apple is looking to bring with this newest version of Mavericks to consumers whenever they launch it publicly, but it’s looking more and more likely that it’s an update geared towards bug squashing, performance tweaking, and overall stability enhancements. Again, Apple is asking developers to focus on USB, Graphics, USB Smart Cards, Thunderbolt and Safari.
The update is available either through Apple’s official developer portal, or through the Software Update option on your Mac running the third 10.9.5 beta.
Of course, along with these betas for developers, Apple is still working diligently on the betas for OS X Yosemite, which is also available in a public beta.