In case you care to do a Samsung Gear application, without an available SDK, you can look at this simple example. For debugging / development I created an emulator from the AVD editor in my android development tools - to match as far as possible the Gear Specification.
Oh, and for further information on resources / sizes / layouts / interface / construction and rest of stuff of the Samsung Gear, you can just use APKTool to unpack the Gear firmware, which you can find (both, tool and firmware) all over the internet. The android that runs on the Gear at the current date, is 4.2.2, just in case you wonder.
If you reuse something or it helped you somehow, glad to help