I am fairly new to iOS and XCode and come from .Net background. So in Visual Studio I would usually separate the layers of my application (say WebApp layer, business logic layer, data access layer etc.) into separate project so I can have control over what each project depends on etc.
So my question is if there is something similar in XCode? I tried using the static library template for a target and it seems to be working but I am wondering if there are any drawbacks for this approach? All the examples I find on the Internet just show a folder structure in the app target for the layers is this the preferred way of doing it and why?
I am also using Swift if that makes any difference but I still do have dependencies on 3rd party libraries developed in Objective-C
New in Xcode 6 / iOS 8, you can make a framework, thus dividing your code into multiple targets. This is a nice easy way to separate reusable functionality. It also has the advantage of privacy; in Swift, each framework is a module, and one module that imports another module can see only those members of the imported module that are declared public.
In general, however, I would suggest that you not worry about this; just keep your classes organized conceptually using the MVC architecture that Cocoa encourages, and physically organize them within your project using "groups" (the fake folders that appear in Xcode's project navigator). The reason is that very little of your code is going to prove to be reusable anyway, so it's really just a matter of making editing / developing / maintaining this project as easy as possible.