Attempted summary clarification for class factory methods in iOS..

Just be clear (and put it precisely as possible):

Objective-C does not have constructor methods that are available in other programming languages.

Thus Factory methods are essentially Objective C's constructor methods.

..and per the iOS docs:

"Class factory methods are implemented by a class as a convenience for clients.

They combine allocation and initialization in one step and return the created object.

However, the client receiving this object does not own the object and

thus (per the object-ownership policy) is not responsible for releasing it."

Is this referring (maybe) to garbage collection?!

So, asking:

"How are factory methods compared to Singletons", you could say:

"A singleton usually offers a single method to return the single instance of the class.

It isn't strictly a factory method as it doesn't create a different instance each time it's called,

but it is (essentially) the same kind of thing"...huh?

Also considering the question of:

"When I should implement the factory method pattern vs an init overload?"

I found an this stackexchange thread:

http://programmers.stackexchange.com/questions/237201/objective-c-style-do-i-implement-factory-methods-or-init-methods

Which said (succinctly)::

"Every class should have a designated initializer, i.e. an instance method whose name starts with "init" that leaves a newly allocated object in a valid state.

You can add other initializers that provide additional functionality, but these should call the designated initializer. You can also create factory methods when that's helpful."

Thus:

• always provide a designated initializer

• provide additional initializers and factory methods if you need or want them