From the Netexl blog: "A very basic requirement for HTML5 games is to be able to scale to the resolution of the device on which the game is running. Since HTML5 games can run both on pc as well as mobile, there are thousands of resolutions and aspect ratios which the game needs to support.
Now this is somewhat hardest part of the development process. I decided to make a game which is responsive, adapts to the screen resolution on both pc as well as mobile, and works for both orientations (Portrait as well as Landscape) in mobile. It did not turn out to be a trivial solution. There is some material available on internet which mostly talks about the concepts but there is not much available out-of-the-box to use and there is no one solution which can be used in handle it.
There are solutions which fit into one type of games but would not work for another. It entirely depends on the requirements of a specific game."