From the moment of Apple's introduction of Swift in 2014, popularity has been on the steady rise. Where you might believe it would be the dominant language today, it is still the up and coming language choice. Recent estimates are that about 75% if apps being developed on the Apple platform are still being done in Objective-C. It's just a case of the newbie verses the dinosaur. The market expectation is that as new developers come into the workforce, they will pick up with Swift verses learning Objective-C. And that remains to be seen but does make sense.
Swift is the latest generation programming language from Apple. It is designed to be the latest and greatest for all of its current platforms and ships with Objective-C libraries making running apps built in C, Objective-C and C++ run in the same application. Swift is designed to work with Apple's Cocoa and Cocoa Touch frameworks as well.
The Sparkfish development team leads with Swift and its protocol-oriented design as it takes extensible markup from Objective-C and moves it ahead of the pack. Swift is open-source so that developers can always look under the hood to understand how it makes the magic happen but more importantly, all that you need to start compiling is Playground App or Xcode. It very much simplifies what's need to get started developing an app. Any development methodology or programming language that reduces complexity and time consumed getting started is always a winner with clients as it creates an overall cost reduction.