What Ruben was asking, is;
Could it be on one device (a Windows PC) you browse to "www.mysite.com".
And another device (an Apple iPad) you browse to "mysite.com".
"www.mysite.com" and "mysite.com" are two different websites.
Further reading at -
http://www.webhostingtalk.com/wiki/URLs_with_or_without_wwwAnd at -
https://support.google.com/webmasters/answer/44231?hl=en