If you are waiting for OS X Mavericks 10.9.3, then you can now test the 4th beta version of this firmware. There are no known issues in this firmware. It comes with a build number 13D28. You must be a developer to download and install the 4th beta version of OS X Mavericks 10.9.3 on your device. Developers are being asked to focus their testing on two areas such as graphics drivers and audio. This firmware is not recommended for all Mac users.
You will need to have a developer account to download OS X Mavericks 10.9.3 build 13D28 as it is available only for registered developers. This is really a great news for the developers who are waiting for it. You have to pay yearly fees for developer account. If you are not a developer, then you will have to wait until the release of OS X Mavericks 10.9.3. Don’t forget to save all your important data before upgrading your device to the 4th beta version. If you are planning to test OS X Mavericks 10.9.3 build 13D28, then you have to go to the Mac Developer Center. The Cupertino company has recently released OS X Mavericks 10.9.2. It allows users to enjoy FaceTime Audio feature on their Mac. If you want to block iMessage and FaceTime users on your Mac, then you can install OS X Mavericks 10.9.2. You will not face any issue with VPN connections after installing it on your device.
If you are planning to enjoy all features of the new firmware on your device, then you should avoid installing OS X Mavericks 10.9.3 build 13D28. You must wait until the release of its final version. You may be able to download OS X Mavericks 10.9.3 after a few months. It will be available in the Mac App Store. You will be able to enjoy several new features on your device after installing it.