FACEBOOK MESSENGER WITH CHAT HEAD IS THE FUTURE
Facebook has just released an update to its Facebook messenger app yesterday, and the app features its chat head feature announced at the Android Home event.
The Chat heads pop up on the phone screen regardless of the app being used (I haven't tried it with videos though), and allows you to respond to messages without leaving your current app.
In my opinion, the chat head is well worth the upgrade and more useful to me than the Facebook Home
I would definitely love to see this feature implemented in competing messaging services such as Whatsapp, as it would enable quick respond to messages and also conversation switching especially when you are conversing with multiple people.