Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
They would be talking about AppDelegate.m

Though you might have to make changes in AppDelegate.h if you will be subscribing to a delegate of some kind. Otherwise you should be fine to just import the class in the .m implementation file and add the code there.

Generally initialization code like that is placed in the didFinishLaunchingWithOptions method.
 
Thanks but I have problems to implement Google Analytics in my app, my fault because I'm new to iOS programming and also because Google tutorial does not seem clear, code gives me error. I'm programming in Objective-C with Xcode 7. you can recommend some good tutorials?
 
I hate to say it, but if you're not sure whether you should be putting code in the header (.h) or the implementation file (.m) you definitely want a more basic course than just a tutorial. I would recommend bitfountain.io for their ios courses, or lynda.com as well, both are pretty good. I'd advise taking a beginner iOS course if you can, before trying to integrate a framework.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.