Apple Changes How OS X Apps Treat Memory With Move To ARC
Apple is ready to ask Developers to make improvements to incoming Mac Apps. Through the Apple Developers portal, Apple is asking OS X Developers to change the way their incoming apps treat memory. Rather than 'Garbage Collection', Apple is asking Developers to use Automatic Reference Counting (ARC) for memory management. The change applies only to incoming apps, and for apps submitted after May 1. Developers should have seen this coming, though; Apple began favoring ARC over Garbage Collection back in the days on OS X Mountain Lion.
For Developers with apps in the works already, Apple is noting it's best to use Xcode's migration tool to transition from Garbage Collection to ARC.
If you're wondering what this means for you as a user, this all has to do with how your apps will treat memory. On a basic level, ARC treats the process of managing your device memory differently, and potentially speeds things up since there's no background process happening. With Garbage Collection, much of the memory management was done automatically, but could cause actions to be put on hold momentarily.
The ARC method does make things a little more tedious for Development, but when done properly, will likely improve app performance. It's also a bit more real-time for memory management.
ARC is the memory management used for iOS, so this is likely a move to streamline memory maintenance.
Source: Apple