Apple Reminds Developers App Updates Must Support 64-Bit Starting June 2018, Warns Customers About Unoptimized Apps

Apple today reminded developers about upcoming changes being made to the Mac App Store. Starting on June 1, all new app updates submitted to the Mac App Store must support 64-bit.

Apple already requires new apps submitted to the Mac App Store to offer 64-bit support, a change that went into effect in January of 2018, so this upcoming policy shift will only affect older apps that have not yet implemented 64-bit support.

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Along with the warning to developers, Apple says customers who are running the latest macOS 10.13.4 update will begin receiving warning messages when launching a 32-bit app for the first time to let them know that the app is not optimized for their Mac. According to TechCrunch, these warnings will start at midnight Pacific Time on April 12.

With the recent release of macOS High Sierra 10.13.4, the first time users launch an app that does not support 64-bit they will see an alert that the app is not optimized for their Mac.

As a reminder, new apps submitted to the Mac App Store must support 64-bit, and starting June 2018, app updates and existing apps must support 64-bit. If you distribute your apps outside the Mac App Store, we highly recommend distributing 64-bit binaries to make sure your users can continue to run your apps on future versions of macOS.

Apple used a similar warning system when phasing out 32-bit support on iOS before eventually ending support with iOS 11, and the company has said the same plan will be used as 32-bit Mac apps are phased out.

Apple first warned developers and consumers about the impending Mac App Store changes starting last June at the 2017 Worldwide Developers Conference. Apple is slowly ending support for 32-bit Mac apps and has said macOS High Sierra will be the "last macOS release to support 32-bit apps without compromises" and "all future Mac software will eventually be required to be 64-bit."

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Top Rated Comments

szw-mapple fan Avatar
95 months ago
Why even bother going to 64 at this point when 128 is right around the corner?

Apple’s stupidity never ceases to amaze.
The sheer ignorance in this comment is as amazing as “apple’s stupidity” is to you. 128 bit OS’s right around the corner? The number of bits refers 2 to the power of that many bits of addressable locations. That means the addressable locations is 4,294,967,296 for 32 bit processsors and over 18,446,744,073,709,551,616 for 64 bits. This in turn means the the most RAM per process we could have for a 32 bit computer is 4GB while for 64 bit, which is about 16 exabytes. It’s more than conceivable that we won’t have need for 128 bit environments for decades to come.

EDIT: clarification about the maximum amount of RAM.
Score: 17 Votes (Like | Disagree)
Baymowe335 Avatar
95 months ago
Why even bother going to 64 at this point when 128 is right around the corner?

Apple’s stupidity never ceases to amaze.
I wish I could be $900B stupid and the most profitable company is history.
Score: 13 Votes (Like | Disagree)
Alexander Becker Avatar
95 months ago
Why even bother going to 64 at this point when 128 is right around the corner?

Apple’s stupidity never ceases to amaze.
I don't think that's the point at all. The point is to push developers to ditch 32. Apple has been in world of 64 for a while.
Score: 11 Votes (Like | Disagree)
york2600 Avatar
95 months ago
I don't think that's the point at all. The point is to push developers to ditch 32. Apple has been in world of 64 for a while.
Apple wants to dump the 32bit libraries from the OS. It's a pretty big win for the development of macOS to rid themselves of that code and maintenance work.

Source: I'm currently sitting waiting on a 32bit build to pop out of Jenkins. It takes 3x longer than my 64bit builds because of "reasons" and constantly holds up our development.
Score: 9 Votes (Like | Disagree)
CptSky Avatar
95 months ago
Could somebody clarify that this will only affect MAS apps and not all Mac apps that are 32 bit? I have some older universal binary 32bit apps that I still want to be able to use, and hopefully they won't be obsolete in two years.
They plan to remove 32 bits support from the OS in the future, it includes non-MAS apps.
Score: 7 Votes (Like | Disagree)
Seoras Avatar
95 months ago
Saw this post and thought "what could I have that's so old it's 32 bit?"
Aha! Microsoft Office 2008 !
Just as well I used it's (32 bit) un-installer while I still could.
Good riddance.
Score: 6 Votes (Like | Disagree)