How to thoroughly test an iOS app created with Swift?

Belonging to the world of web development, I am used to powerful testing techniques and tools like Chai, Sinon, Mocha, Jasmine, to name a few, as well as to wide support and community, well-written books with deep insights.

Now, learning iOS development with Swift, I wonder, how I can thoroughly test methods of my app using stubs and mocks, imitating connecting to web services asynchronously and get myself sure tests can be written in a clear manner, creating peace of mind for my aging body.

I find the community is not so wide in iOS development, especially, Swift, as a result of the language being not so long on the landscape.

Please share the best practices for testing that can help me to create solid predictably behaving apps.