We've developed several sample extensions that demostrate the use of the InboxSDK. The examples are all hosted on GitHub. If you'd like to help develop more samples, let us know!
Note that reactive libraries often contain many specialized functions for creating streams from timers, event listeners, and other streams. This example purposefully uses a general method instead that can be quickly adapted to many uses. The above example should be enough to show you how to interact with the InboxSDK's stream-compatible methods, but if you want more information on reactive streams in order to use them more effectively, some recommended resources include the documentation of the above libraries, Netflix's talk on Reactive Programming, and The introduction to Reactive Programming you've been missing.
Chrome and Safari are currently supported. Chrome version 36 and Safari 10 are the minimum versions we support. Firefox support is under consideration; please let us know if you're interested.