AWS IoT is the most popular IoT platform.

With AWS IoT,
  • remote devices can be connected to the AWS cloud
  • applications can interact with remote devices
  • data can be collected from remote devices and be processed in the AWS Cloud
  • users can control devices remotely

AWS IoT: How It Works
  1. A device publishes a message which is sent to the Message Broker.
  2. Message Broker sends message to all subscribed clients.
  3. Rules Engine performs actions (by calling AWS services) based on messages.
  4. Device Registry stores device information and security certificates.
  5. Device Shadow stores and retrieves device state information.
  6. A device can be controlled by changing its state.