Earlier this week, Apple released the fourth developer preview of OS X 10.10 Yosemite, two weeks after the availability of developer preview.

The new Mac OS X beta is available via Mac App store Software Update for developers running the previous versions of Yosemite.

Like the previous Preview versions, which add several design tweaks and feature enhancements, the Developer Preview 4 also integrates a few changes, such as redesigned Calculator app and the ability to dial out to any phone number using the Facetime app.

Yosemite Beta Goes Public

Apple have also seeded OS X 10.10 Yosemite builds to a million of beta programme members. Users who have signed up for the OS X Yosemite Beta programme will receive a download code.

But a number of users reported an error which says the code has been redeemed, reports 9to5Mac. Nevertheless, Apple has acknowledged the issue and posted a fix for this.

Fix: Refresh the beta programme redemption page while signing in. Refreshing the page should generate a new code which will work in the Mac OS App Store.

The beta programme, as Apple notes, will not be updated as often as the developer version. But members will be able to upgrade to the final public version of Yosemite via the App Store.