Allow cloud applications to interact with connected devices even when they are offline (Device Shadows) – AWS IoT would create a persistent, virtual version, or “shadow,” of every device that stores the latest state of a device so that applications or other devices can read messages from the device and interact with it anytime – even if it is offline. By providing always-available REST APIs, AWS IoT would make it easier for customers to build applications that interact with connected devices. Applications can read the state of a device or set a desired future state through API calls, and AWS IoT takes care of setting the correct state, sending only relevant changes to the device once it reconnects.