Smartface App Studio is incredible! Samsung currently not being shared SDK for Gear, but you can develop your apps for Gear with using Smartface App Studio.
How to Develop?
Everything is almost the same as Android development with App Studio. Just take care few points.
1) Just choose Galaxy Gear screen resolution from Project Details.
2) Delete the Android location services permission from AndroidManifest.xml of your project.
3) Get .apk package from App Studio and send it to Samsung Gear via adb.
You can checked detailed information here.