Usage with UI Frameworks
Both redux and redux-observable are UI framework agnostic. Not only can you pick your favorite one, if you decide to change UI frameworks down the road, a majority of your business logic will be in redux + redux-observable so your UI framework is mostly just a view layer/template, making it much easier to switch between them!
Here are some JSBins to get a general feel for how you might use redux-observable. Keep in mind that these aren't necessarily suggestions on how you should structure your code.