Apple’s Swift 5 will make many iOS apps smaller

“The most significant change to Apple’s developer ecosystem this decade has been the introduction of the Swift programming language – and we’ll probably see the next big change come during this year’s WWDC with the introduction of third party UIKit apps on the Mac,” Guilherme Rambo writes for 9to5Mac.

“An important aspect of Swift that has been affecting users since its first version is that its application binary interface, or ABI, is not stable. What that means in practice is that Apple can’t include the Swift language support in its operating systems, because an app written with Swift 3 won’t work with the language support binaries for Swift 4. The solution to that is to include the Swift language libraries inside the app bundle that gets downloaded from the App Store, increasing the bandwidth and storage required by the app,” Rambo writes. “That’s finally changing.”

“With Swift 5, the language becomes binary compatible,” Rambo writes. “The new version is included in iOS 12.2, tvOS 12.2, watchOS 5.2 and macOS 10.14.4, all of which are currently in developer beta. This means that, when the new versions of Apple’s operating systems become available to the general public, apps published to the App Store which use Swift 5 are going to be significantly smaller for users running the new operating systems.”

Read more in the full article here.

MacDailyNews Take: So, as users update their OSes and developers update their apps sign Swift 5 (the former will be much quicker than the latter) app sizes will decrease and launch times will increase; a win-win!


  1. “…apps sign…” Apps with?
    “(The former will be much quicker that the latter)”
    The LATTER will be (smaller and faster to download) than the FORMER?

    Hmm…tapping those kegs piss heads???

    1. English translation suitable for Russian trolls: the adoption of the new operating systems by users will happen long before most developers go back and recompile all their apps using Swift 5.

      1. no recompiling necessary, swift 5 automagically “uncouples” the version specificity of the code, so it plays what is called “binary compatible” so it is only going to get better no matter what the developer of the app decides to do

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