We don't have a UWP SDK, and UWP apps aren't allowed to use normal interprocess communication -- which is what allows an app to get data from the Leap Motion service.
However, we do work with SteamVR, and UWP supports SteamVR. Build for SteamVR, and you're golden.
If UWP is absolutely necessary, you need to pass the hand tracking data from the API into the UWP sandbox. This can be a difficult undertaking.