This is somewhat true, and frustrates me to no end as someone who builds web video stuff. For what it's worth it's only somewhat true. If you exit the browser while video is playing, the video is paused. If you then go to the Media Notification that Chrome added for the video and hit play, it will continue playing in the background.
The same is true on iOS, but using the media center instead of the media notification, in which case it will work.
On Android native apps this isn't really true at all, but you should use a background service to handle playback to avoid getting killed by the OS on low memory situations.
This does not work for YouTube on the web, because they simply use the web visibility API to stop you from resuming the video if you try, unless you have premium.
The same is true on iOS, but using the media center instead of the media notification, in which case it will work.
On Android native apps this isn't really true at all, but you should use a background service to handle playback to avoid getting killed by the OS on low memory situations. This does not work for YouTube on the web, because they simply use the web visibility API to stop you from resuming the video if you try, unless you have premium.