The first part of the system is a hub that forms the bridge between the Internet and home devices supporting low-power, wireless protocols like Zigbee and Z-wave. SmartThings adds a set of reference devices to that: a motion sensor, a contact sensor that can be attached to doors and windows, and a low-resolution cloud-controlled camera. You can also use standards-based devices from other manufacturers. Finally, there’s the SmartTag, a keyfob that indicates your presence and also acts as an environment sensor. All kinds of apps will run on top of the basic platform.