Recs.
Updated
SpecsUpdate
Pros
Pro Full stack language: write the (mobile) client & backend in the same performant language
Pro Swift is closer to other platforms
Apple’s modern programming language is easier to understand for non-iOS developers and minimizes time for additional explanations and clarifications. Moreover, Swift can be used as a script language. It is an interesting solution for the iOS community to unify writing of build scripts. At the time being iOS developers are split up in regard to this activity. Some of them write build scripts in Bash, others use Ruby, Python, etc. Swift gives an amazing opportunity to be applied to all iOS programming needs.
More details can be found here https://mlsdev.com/blog/51-7-advantages-of-using-swift-over-objective-c
Pro No garbage collection pause
For example in the JVM (Java) or the CLR (C#) it's possible that your running code is paused while in the background memory is freed which is not the case with Swift
Pro One of the fastest growing languages
If not the fastest, it could very well be the server-side language of the future, maybe even dethroning Java in the long run.