The advent of multi-touch devices in the form of smart phones and tablets has meant that we rely on more gestural interactions. This makes it a little more difficult to capture the different interactions in workflow sketches and wireframes. I know I’ve worked on a few projects where I’ve found it a challenge to convey the different interactions and their consequences without a large paragraph of text.
I came across this lovely set of icons from Mobile Tuxedo. They are pretty comprehensive and look very clean and refined. Best of all, they are royalty free for personal or commercial projects.