I have made HTML5 canvas game for mobile phones. It resizes dynamically to accommodate for different screen sizes. You can have a look at it:
[login to view URL]
It has a login page and on mobile phones if any input field on this page is under focus, the virtual keyboard appears and changes the screen size. The game is made on canvas and I have added a form with position fixed to overlay on this canvas. When virtual keyboard appears the canvas adjusts smartly but the input fields are distorted. I have an image to explain the problem.
Please open the website on PC and resize your browser window to see that the game has a relative layout and changes according to the screen size but when on mobile browser, the login page gets distorted.