Merging

A common task done in ReactiveX is taking two or more Observable<T> instances and merging them into one Observable<T>. This merged Observable<T> will subscribe to all of its merged sources simultaneously, making it effective for merging both finite and infinite Observables. There are a few ways that we can leverage this merging behavior using factories as well as operators.

Observable.merge() and mergeWith()

The Observable.merge() operator will take two or more Observable<T> sources emitting the same type T and then consolidate them into a single Observable<T>.

If we have only two to four Observable<T> sources to merge, you can pass each one as an argument to the Observable...