The third public beta of Apple’s upcoming operating system OS X El Capitan was released to public testers today, one week after the release of El Capitan beta 2. The new operating system was announced at WWDC last June, was first made available to public tests earlier this month.
The release notes didn’t mention any major new features however mostly like a number of bug fixes and performance improvements. If you are still on public beta 2 and face some issues with bugs and performance, recommend you to get new update via App Store on your Mac anytime. You can check out what upcoming OS X El Capitan looks like on Mac here.
For first time public beta tests can sign up for the new OS X El Captain Beta via Apple Beta Software Program which is found via link in the below. You also can get iOS 9 beta for your iOS devices if interested. Once registered, El Captain can be installed on your Mac. If you prefer to have full software, can wait till both OS X El Capitan and iOS 9 come out this Fall.
Source: Apple Beta Software Program