Apple Seeds Third macOS Sierra 10.12.1 Beta to Developers

Apple today seeded the third beta of an upcoming macOS Sierra update to developers for testing purposes, nearly one week after seeding the second beta and two weeks after releasing the new macOS Sierra operating system to the public.

macOS Sierra 10.12.1 beta 3 can be downloaded from the Apple Developer Center or through the Software update mechanism in the Mac App Store.

macossierra
macOS Sierra 10.12.1 appears to focus on bug fixes and under-the-hood performance improvements to address issues that have been found since the operating system's release. Few outward-facing changes were discovered in the first two betas, but it does include Photos support for the new iPhone 7 Plus Portrait feature introduced with iOS 10.1. New features discovered in the third 10.12.1 beta will be listed below.

macOS Sierra is a significant update that brings features like Siri support, a new storage optimization option, cross device copy paste, auto unlocking with the Apple Watch, and more. For full details on macOS Sierra, make sure to check out our roundup.

Related Forum: macOS Sierra

Popular Stories

iOS 26

15 New Things Your iPhone Can Do in iOS 26.2

Friday December 5, 2025 9:40 am PST by
Apple is about to release iOS 26.2, the second major point update for iPhones since iOS 26 was rolled out in September, and there are at least 15 notable changes and improvements worth checking out. We've rounded them up below. Apple is expected to roll out iOS 26.2 to compatible devices sometime between December 8 and December 16. When the update drops, you can check Apple's servers for the ...
Foldable iPhone 2023 Feature 1

Apple to Make More Foldable iPhones Than Expected

Tuesday December 9, 2025 9:59 am PST by
Apple has ordered 22 million OLED panels from Samsung Display for the first foldable iPhone, signaling a significantly larger production target than the display industry had previously anticipated, ET News reports. In the now-seemingly deleted report, ET News claimed that Samsung plans to mass-produce 11 million inward-folding OLED displays for Apple next year, as well as 11 million...
iPhone 14 Pro Dynamic Island

iPhone 18 Pro Leak Adds New Evidence for Under-Display Face ID

Monday December 8, 2025 4:54 am PST by
Apple is actively testing under-screen Face ID for next year's iPhone 18 Pro models using a special "spliced micro-transparent glass" window built into the display, claims a Chinese leaker. According to "Smart Pikachu," a Weibo account that has previously shared accurate supply-chain details on Chinese Android hardware, Apple is testing the special glass as a way to let the TrueDepth...
iOS 26

Apple Seeds Second iOS 26.2 Release Candidate to Developers and Public Beta Testers

Monday December 8, 2025 10:18 am PST by
Apple today seeded the second release candidate version of iOS 26.2 to developers and public beta testers, with the software coming one week after Apple seeded the first RC. The release candidate represents the final version iOS 26.2 that will be provided to the public if no further bugs are found. Registered developers and public beta testers can download the betas from the Settings app on...
iPhone 17 Pro Cosmic Orange

10 Reasons to Wait for Next Year's iPhone 18 Pro

Monday December 1, 2025 2:40 am PST by
Apple's iPhone development roadmap runs several years into the future and the company is continually working with suppliers on several successive iPhone models at the same time, which is why we often get rumored features months ahead of launch. The iPhone 18 series is no different, and we already have a good idea of what to expect for the iPhone 18 Pro and iPhone 18 Pro Max. One thing worth...
Johny Srouji

Apple's Chipmaking Chief Johny Srouji Responds to Report About Him Potentially Leaving

Monday December 8, 2025 9:23 am PST by
Apple's chipmaking chief Johny Srouji has reportedly indicated that he plans to continue working for the company for the foreseeable future. "I love my team, and I love my job at Apple, and I don't plan on leaving anytime soon," said Srouji, in a memo obtained by Bloomberg's Mark Gurman. Here is Srouji's full memo, as shared by Bloomberg:I know you've been reading all kind of rumors and...
Google maps feaure

Google Maps Quietly Added This Long-Overdue Feature for Drivers

Wednesday December 10, 2025 2:52 am PST by
Google Maps on iOS quietly gained a new feature recently that automatically recognizes where you've parked your vehicle and saves the location for you. Announced on LinkedIn by Rio Akasaka, Google Maps' senior product manager, the new feature auto-detects your parked location even if you don't use the parking pin function, saves it for up to 48 hours, and then automatically removes it once...
Johny Srouji

Apple Chip Chief Johny Srouji Could Be Next to Go as Exodus Continues

Sunday December 7, 2025 10:41 am PST by
Apple's senior vice president of hardware technologies Johny Srouji could be the next leading executive to leave the company amid an alarming exodus of leading employees, Bloomberg's Mark Gurman reports. Srouji apparently recently told CEO Tim Cook that he is "seriously considering leaving" in the near future. He intends to join another company if he departs. Srouji leads Apple's chip design ...
google pixel 10

Switching Between iPhone and Android Will Get Easier With New Apple and Google Collaboration

Monday December 8, 2025 11:10 am PST by
Apple and Google are teaming up to make it easier for users to switch between iPhone and Android smartphones, according to 9to5Google. There is a new Android Canary build available today that simplifies data transfer between two smartphones, and Apple is going to implement the functionality in an upcoming iOS 26 beta. Apple already has a Move to iOS app for transferring data from an Android...
Intel Inside iPhone Feature

Apple's Return to Intel Rumored to Extend to iPhone

Friday December 5, 2025 10:08 am PST by
Intel is expected to begin supplying some Mac and iPad chips in a few years, and the latest rumor claims the partnership might extend to the iPhone. In a research note with investment firm GF Securities this week, obtained by MacRumors, analyst Jeff Pu said he and his colleagues "now expect" Intel to reach a supply deal with Apple for at least some non-pro iPhone chips starting in 2028....

Top Rated Comments

forerunnerg34 Avatar
120 months ago
Yes, but...
Score: 25 Votes (Like | Disagree)
blacktape242 Avatar
120 months ago
I wish i could unsee that.....


Sierra 10.12.1 on Late 2016 MacBook with Fusion 3D Touch trackpad.





Score: 12 Votes (Like | Disagree)
smacrumon Avatar
120 months ago
Sierra 10.12.1 on Late 2016 MacBook with Fusion 3D Touch trackpad.




Score: 5 Votes (Like | Disagree)
keysofanxiety Avatar
120 months ago
It's the one OS Apple makes that isn't designed for babies or really old people, the two target groups who get confused by a real file management system
There was a time when people said similar things about a graphical operating system.

And there are plenty of people whose iPads help them to achieve incredible work. Industries such as science, medicine, graphic design — you know, those industries that are dominated by babies and really old people.
Score: 5 Votes (Like | Disagree)
jclo Avatar
120 months ago
in the last few betas I have seen zero difference or anything new or better, what are they actually changing
Presumably features that will be supported in the new MacBook Pro. It's meant to be sent off to the factory shortly to be installed on new machines.
Score: 4 Votes (Like | Disagree)
MrGimper Avatar
120 months ago
Going into courage overdrive.
Score: 4 Votes (Like | Disagree)