Apple making sparse use of Swift in its own apps, engineer claims
In spite of Apple expressing a desire to switch its apps to Swift, just a handful of them are actually using the programming language so far, according to a software engineer.
The Calculator app is the only part of iOS 9.2 that includes any Swift code, Ryan Olson noted in a blog post. It is at least said to be nearly "pure" Swift, with only two of 22 classes written in Apple's previous favorite language, Objective-C.
Even Apple apps that are optional downloads from the App Store are generally reliant on Objective-C, Olson added. The official WWDC app makes use of some Swift, as does the Apple Store app's Watch interface, but even the former only contains Swift in six out of 281 classes.
The problem likely stems from several issues, such as the Swift Application Binary Interface not being finished. This should happen by Swift 3, but until then app compatibility may be too prone to breaking. There's also no 32-bit Swift runtime for OS X.
In December Apple's senior VP of Software Engineering, Craig Federighi, said that El Capitan's Dock and window management code was done with Swift, and that the iCloud team is "champing at the bit" to try the language. Deeper integration may have to wait until newer iOS and OS X releases later this year.

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I say iOS 11 will be the first major release with more Apple apps using the language.
Apple's recent open-sourcing of Swift could lead to broader adoption at Universities, even if they don't have Mac hardware. (... once Swift compilers & IDEs are available on other platforms)
John Gruber: How do you manage as the chief mofo in charge of this? How do you manage the enthusiasm that you clearly have for Swift and, what to me seems like a sincere belief that Swift is the way forward — with the necessary conservativeness that you need so that there still has to be a lot of Objective-C written? How aggressive can you be about putting teams on, “Sure, go ahead and do that in Swift”?
Craig Federighi: People here are idealistic yet really pragmatic, and I think you see that as an Apple characteristic in many, many elements of what we do. And so, teams know, what the nature of what we’re trying to get done in their area in any given year, the nature of their code base, whether Swift is the right answer for them, or where it’s the right answer. Even teams where, for one reason or the other, they can’t jump right on Objective-C — or rather Objective-C conversion to Swift now. They then use Swift heavily for writing all their unit tests, which is great because then at least as they’re introducing new APIs, they’re experiencing their own APIs in Swift and then … sort of eating their own dog food in that regard. We do have some constraints internally which we’re addressing, but because we … I mean, it’s something in our closet a little bit, but we still support running 32-bit apps on the Mac. And the 32-bit runtime doesn’t actually support Swift right now. And so, what that means is that if we implement a framework that’s available to 32-bit code, we actually can’t write it in Swift. If that code, if that framework is used across iOS and OS X — as many of our frameworks are — that introduces a little stumbling block as well. So teams recognize what’s practical and what’s not practical and find ways to use Swift wherever they can. There’s no shortage of enthusiasm.
Read the post above from UnitedWorx and ask yourself why you can't grasp reality like he does, and Craig and Gruber and by implication Tim Cook do, and why you're such an emotional basket case that no one of reason can take you seriously.
But I must ask... who would be a "better" CEO? You know Steve Jobs chose Tim Cook as his successor, right?
One problem, however is that Swift is a young language that is evolving rapidly ...
Apple, IBM, educators, publishers and the open source community must assure that their content keeps pace with the Swift language evolution!
Still, Swft is less than 2 years old and, I suspect, has better acceptance than any other language at that young age. For Example CoBOL took 10 years:
https://en.wikipedia.org/wiki/COBOL#History_and_specification
Isnt Tim showing "Jobs" like behaviour and not giving a toss about wall street and just running the biggest and most profitable company in the world?
Isn't Apple making more money than they know what to do with it?
Isn't Apple launching products every year that sale like hot cakes?
Isn't Apple leading a cut throat sector and is considered to be the leader and closely followed by all the others?
Isnt Apple raking it by cornering the "premium sector" and having 90%+ of the profits in both mobile and "proper" PC's?
ok you've convinced me he's a bloody useless CEO. Maybe they should go private /s
Same rights for everyone independent on who you are. Sounds very progressive to me and by setting this new standard, I hope many companies will follow. Wall Street has never understand Apple so why bother. They show time after time again investors were wrong. And if Apple doesn't beat record after record, I'm still proud on their forward thinking and hope someday the critics might too. I'm no native English speaker so I do apologize for the typos.
The important thing in a system development is that it works near 100%
For the UI portion, that's not as critical, you can have a few bugs.
Porting introduces new bug so they would only use swift in brand new development, modules, API's, etc.
Someone creating a new App on IOS would in a sense be doing "new development", for them it is a no brainer.
Also, people that have coded something in language X will not suddenly switch it all in language Y for kicks; that would be idiotic.
Not only that, in effect, he was in charge for the last few years (while Jobs was mostly focused on development).
All the app developers I know are facing the same struggle to use Swift all the way, which means in practice that for iOS development we are still sticking to the ugly and inefficient ObjectiveC until Swift has stabilized
First, that's "...is late in implementing it." "-ing" not "-ed". Watch your tenses, or people might start thinking your opinions are those of an uneducated fool.
Second, the majority of Wall Street's issues are with Apple, not Cook. Wall Street's afraid that Apple's a one-trick pony and that iPhone sales are going to crater any decade now. Their next biggest issue lies with how Apple goes its own way and totally fails to acknowledge their sage pronouncements and suggestions on what Apple needs to do to become a "successful" company.
Despite being the most successful company in the world.
Third, everyone else is afraid of the same things, which makes for a "skittish" market in Apple stock. Just one supply chain rumor is enough to send it sliding. "The end is nigh! Then end is nigh!"
Given those facts, it seems to me that you have an obsession with Cook, the person, as opposed to Apple, the company.
I wonder why...
Don't worry, I'm not really expecting a reply.