I looked into Objective C a bit last year but couldn't wrap my head around a lot of conventions. Swift on the other hand I'm looking forward to.
That tutorial looks like it'll help :)
I just can't wrap my head around complex JavaScript-based projects. I was working on a PhoneGap-based mobile app last year and it was a pain to develop and debug.
I've been hearing lots of good stuff about node.js though, so I might have to give it a try eventually and that tutorial looks neat.