Samsung’s Galaxy S5 may be the talk of Mobile World Congress this year, but hidden away in a smaller trade show booth the company is also demoing a phone running Tizen, the open-source operating system the South Korean company may one day use to challenge Google’s dominant Android OS. The elusive Tizen smartphone has seen countless delays over the past year, and while it may be on display in Barcelona there’s still no guarantee the device will hit the market any time soon.

While the new market-ready Gear 2 and Gear Fit both run a scaled-down version of Tizen, Samsung doesn’t think the time is right to launch a smartphone running the new OS. “We are carefully evaluating the market needs and opportunity to introduce the Tizen-based smartphone during this year,” Samsung marketing exec Young-hee Lee told CNET. Apparently the first Tizen phone is ready to go, a second exec says, but the company hasn’t decided when the new OS should make its debut.

Ars Technica managed to get its hands on Samsung’s demo Tizen smartphone, and came away impressed with what they describe as a “capable Android clone” with a few clever new features. The latest version of Tizen offers the same familiar app drawer found on Android as well as a similar home screen, pull-down setting menu and multi-tasking capability to the UI Samsung offers with the Galaxy S5.

Where Tizen really shines is its widgets, which do more than the ones on Android. First off, each widget is expandable. Pull down on the weather one, for example, and you’ll see a multi-day forecast slide out. Samsung’s also done something extremely clever by combining widgets and apps icons. Just like on Android, you can resize your widgets at will, but shrink it down to a 1 x 1 square and it becomes a simple icon. Stretch it back out and you’ll see a full widget. A short video shot by Ars Technica makes the transition look completely fluid.

Based on this latest walkthrough the first Tizen looks pretty appealing, but if there’s one thing holding Samsung back it’s apps. The current Tizen app store offers a decent selection, but has some glaring holes including Google’s suite of apps—which will likely never be allowed to run on Tizen if the search giant has its way. Still, if Samsung offers a sleek enough experience maybe consumers won’t notice what they’re missing.