Update:
From @lopar’s comments a better way would be:
Observable.from(items).publish(publishedItems -> publishedItems.limit(1).concatWith(publishedItems.skip(1).debounce(1, TimeUnit.SECONDS)))
Would something like this work:
String[] items = {"one", "two", "three", "four", "five"};
Observable<String> myObservable = Observable.from(items);
Observable.concat(
myObservable.first(),
myObservable.skip(1).debounce(1, TimeUnit.SECONDS)
).subscribe(s ->
System.out.println(s));