14 DAY TRIAL // One week after the first Beta releases, Apple seeded today a second set of Beta builds of the upcoming iOS 10.2.1 and macOS Sierra 10.12.3 operating systems to developers enrolled in the company's Apple Developer program.
Tagged as builds 14D15 for iOS 10.2.1 Beta 2 and 16D17a for macOS Sierra 10.12.3 Beta 2, the new development versions are here to improve the stability, compatibility, and security of your Mac, iPhone, iPad, or iPod touch device. In the meantime, the forthcoming tvOS 10.1.1 operating system has not received a new Beta milestone.
If you're already using the first Beta builds of macOS Sierra 10.12.3 or iOS 10.2.1 on your registered devices, you are urged to update to today's Beta 2 release as soon as possible. While iOS 10.2.1 Beta is installable through the built-in update system of iOS, you can install macOS 10.12.3 Beta 2 using the Sierra Developer Beta Access Utility.
Most probably, in the next 24 hours, Apple will seed the Public Beta 2 releases of the upcoming iOS 10.2.1 and macOS Sierra 10.12.3 operating systems for the rest of the world who doesn't have a registered and actively paid developer account. Though, we don't recommend installing these if you want to have a stable iOS or macOS experience.
As for the changes implemented by Apple's engineers in these new development releases, it appears that the Cupertino company hasn't published anything yet. As such, we can only assume there are only security fixes and small under-the-hood improvements. We'll update the story when the Public Betas are out.
Update: As promised, we've updated the story on December 21, 2016, to inform our readers that the iOS 10.2.1 Public Beta 2 and macOS 10.12.3 Public Beta 2 builds are now available for everyone who wants to test drive the upcoming operating systems. Also today, Apple seeded the first Beta of watchOS 3.1.3 to developers.