@smilefoto:
You may test how your design works on any device with a free service at http://www.responsinator.com; just write your site URL into Responsinator and you will see the results for a number of devices. At least http://www.smilefoto.se does not seem to work fully ok on small screens - so the design itself is not responsive :(
There is one simple addition to you theme's style.css file which you will find in theme's root folder
/*******************************
limit image width to max. 100%
******************************/
img {
max-width: 100%;
}This will make sure none of your images will not flow over on small screens.