How do I add a close command to multiscreen layouts?

I need to add a close command multiscreen HTML5 screen layouts that will work on multiple platforms and browsers. I have 3 screen layouts defined: Desktop, Tablet, Mobile. These are called by a responsive design web application and display based on the screen width of the platform calling the help. My problem is that there is a requirement to be able to close the help. To do this I have added the javascript code:

</a>

       <a href="javascript:window.close()" class="wPrintButton"><img

       src="Close.png" alt="" class="wPrintButton" border="0" />

in each of the layouts to allow the user to close the help browser tab/window.

My Desktop layout is based on the stock desktop. I added this command Topic.slp and SearchResults.slp d just to the right of the Print icon.

My Mobile lay out is based on the stock iPhone. I added this as an additional row in the homepage links to the Home.slp.

My Tablet layout is based on the stock iPad. Again I added this as an additional item to the homepage links to the Home.slp.

My problem is - it appears that the window.close() javascript will not work with iOS. Has anyone incountered a similar problem and how did you deal with it?