Not 5-8, there are 10 different components/Objects are being used within the ReactiveCocoa framework:
Streams, are monads, represented by the RACStream abstract class, is any series of object values
Signals, represented by the RACSignal class, is a push-driven stream
Subscription, a subscriber is anything that is waiting or capable of waiting for events from a signal
Subjects, represented by the RACSubject class, is a signal that can be manually controlled
Commands, represented by the RACCommand class, creates and subscribes to a signal in response to some action
Connections, represented by the RACMulticastConnection class, is a subscription that is shared between any number of subscribers
Sequences, represented by the RACSequence class, is a pull-driven stream
Disposables, the RACDisposable class is used for cancellation and resource cleanup
Schedulers, represented by the RACScheduler class, is a serial execution queue for signals to perform work or deliver their results upon
Value types, a few miscellaneous classes, such as:
RACTuple
RACUnit
RACEvent
Which ones you wish to be updated/altered in the above components? Also, currently which ReactiveCocoa framework's extension is being used in your code base, Objective C or Swift?
Overly, I am so much familiar with the ReactiveCocoa framework's Design Guidelines and comprehensive list of reasons( Apple Appstore Review Guidelines documents) that can lead to your app's rejection in the review process.