Im french, and im not really really good in English, but it very good understandable !
I made the 4 first levels and I understand everything, better than a French tutorial !
The only thing you can change in your app is : per example, if I am in the Arrays level and I want to change level, I press the Back button but I find my self on the first level, "Swift Basics" !
Can you modify this to be on the level that we left ?
But a really good app to learn Swift !
fredericdinand about Swifty: Learn to code tutorials for Swift, v1.3