When watching a livestream on twitch.tv I noticed that when you press the back button the stream simply minimises to the bottom left corner with a smooth animation, you can then navigate around twitch with it always minimised. It doesn't even seem like the page refreshes and that video player element never refreshes even though everything else is completely changing.
Can someone explain how they are doing this?
It's done using a single page application. https://en.m.wikipedia.org/wiki/Single-page_application