We wouldn't say iriver is pulling out all the stops on its new K1 Smart HD player, but it's certainly putting a bit more love and polish into the device than we've seen from the company in recent months. Now a video of the UI has been unearthed, which shows a new touchscreen UI based on a sort of "circles" concept. There are smacks of a traditional grid and multi-homescreen interface as well, akin to iPhone or Android, with a bit of widget engine and exciting translucent overlays for good measure. A Cover Flow-styled music browser can actually be navigated through use of the accelerometer, and if you're brave enough you can even dive into regular old Windows CE for exciting hijinks. Check the quick demo after the break.