Usually, real-time web-apps are built with websockets, right?
Well, let me be radical here - what if I used Ajax?
Okay, okay, I know it has its limitations. You can't build Agar.io, sending data packets up to fifty times a second, with latency in the milliseconds.
But what about an app that had real-time updates that were a bit less frequent. Maybe receiving notifications with in a few seconds, or a turn-based game?
Is it acceptable to use Ajax.post() every, say, few seconds to receive updates from a, say, PHP script, getting information from an SQL database? As opposed to either RTS games, or the Stackexchange model, where information is loaded when the page is loaded, instead of while the page is open.
So would there be any issues with using this model? Would it lag the client's computer or have some problem related?