How can you combination of push and pull?

  1. How can u do combination of pull vs push? Pushing is done by long poll and poll by normal poll.So will u be sending two requests for push and pull?How will u merge results at client side?

2.How to notify users of new data? By push as mentioned, then will it be a separate long poll request from above?Course says ,for new data we can push to desktop and pull for mobile,its not clear what to do when?