Apple Seeds Fourth macOS Sierra 10.12.1 Beta to Developers and Public Beta Testers - MacRumors
Skip to Content

Apple Seeds Fourth macOS Sierra 10.12.1 Beta to Developers and Public Beta Testers

by

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

macOS Sierra 10.12.1 beta 4 can be downloaded from the Apple Developer Center or through the Software update mechanism in the Mac App Store for those who already have an earlier 10.12.1 beta installed.

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, and it's also likely adding features designed for next-generation MacBook Pro models set to be released later this year.

Few outward-facing changes were discovered in the first three 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 fourth 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 27 Next to iPhone

Here's When iOS 27 Rolls Out Today in Every Time Zone [Update: It's Out]

Sunday September 13, 2026 3:00 am PDT by
Update 10:04 a.m.: iOS 27 is rolling out now, though it may take a bit for all users to see it, so keep checking! Apple is about to release iOS 27, which will finally deliver more advanced Siri AI capabilities as well as a variety of other refinements, improvements, and new features to iPhones. It's Apple's biggest software update of the year, and Apple announced at Wednesday's iPhone event...
Read Full Article • 151 comments
iOS 27 Icon iPhone

iOS 27 Available Today With These 8 New Features

Monday September 14, 2026 9:00 am PDT by
Update: Apple has released iOS 27. During its iPhone 18 Pro and iPhone Duo event last week, Apple announced that iOS 27 will be released widely on Monday, September 14. iOS 27 should be available around 10 a.m. Pacific Time / 1 p.m. Eastern Time today via the Settings app, under General → Software Update. Below, we have highlighted eight new features and changes coming with iOS...
Read Full Article • 111 comments
deep black iphone 18 pro

Apple Says iPhone 18 Pro Max Sold in U.S. Differs in One Way

Saturday September 12, 2026 3:27 pm PDT by
As noted by Nicolas Lellouche, who writes for the French tech website Numerama, Apple has updated its tech specs pages for the iPhone 18 Pro and iPhone 18 Pro Max to clarify which models are equipped with its new C2 cellular modem and where. Apple now says the iPhone 18 Pro has a C2 modem worldwide, while the iPhone 18 Pro Max uses the chip in every country except for the U.S. According...
Read Full Article • 137 comments

Top Rated Comments

Jeremy1026 Avatar
Jeremy1026
130 months ago


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 ('https://www.macrumors.com/roundup/macos-sierra/').
We get it.
Score: 25 Votes (Like | Disagree)
E
edgonzalez32
130 months ago
Remember when Apple used to make computers? So sad those days have passed. Been waiting a year for an updated MBP and will probably have to give up and buy a PC instead. Sad tears.
I mean, just wait a couple weeks. How bad do you need one? And why does it seem like everyone here needs a new Mac every 3 years? My 2007 MBP lasted all the way until 2013. I'm now using a 2013 rMBP, everything maxed out and I don't see myself buying a new Mac until at least 2020. What else could I possibly need?
Score: 17 Votes (Like | Disagree)
jmh600cbr Avatar
jmh600cbr
130 months ago
BRING ON THE MACS
Score: 9 Votes (Like | Disagree)
SamVilde Avatar
SamVilde
130 months ago
I mean, just wait a couple weeks. How bad do you need one? And why does it seem like everyone here needs a new Mac every 3 years? My 2007 MBP lasted all the way until 2013..
Oh, so you know exactly what it's like to be sitting here with an awesome much-loved 2008 MacBook, with its outdated and degraded screen, replacement battery barely able to hold an hour charge, refreshing the MacRumors feed because there's no way we're paying full price on an already-outdated upgrade a month before the launch of something better, and because after 8 years we really do deserve an improved machine in exchange for our frugality and patience. You know what it's like to be in this position.

How badly do I need one? I can wait a few weeks. I can wait a few months if I have to. But I don't feel like I'm being pathetic in wanting a replacement.
Score: 7 Votes (Like | Disagree)
ipodlover77 Avatar
ipodlover77
130 months ago
Any hints towards the new macs?
Score: 7 Votes (Like | Disagree)
P
peterh988
130 months ago
Any hints towards the new macs?
Once again, seeing the stock image used to illustrate these articles gave me a little flutter.

Followed by the depression upon realising its about the OS again. :(
Score: 6 Votes (Like | Disagree)
Read All Comments