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

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

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Top Rated Comments

Jeremy1026 Avatar
114 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)
edgonzalez32 Avatar
114 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
114 months ago
BRING ON THE MACS
Score: 9 Votes (Like | Disagree)
SamVilde Avatar
114 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
114 months ago
Any hints towards the new macs?
Score: 7 Votes (Like | Disagree)
32828870 Avatar
114 months ago
Interesting to see if Siri will handle HomeKit...

...and new Mac's? Maybe? No? Prada Watchbands?

Score: 6 Votes (Like | Disagree)