Equipment (i.e., hardware and software) other than the primary device that can be hosted remotely, locally, or on other equipment (e.g., a mobile app on the customer’s smartphone) that supports the IoT device in its functionality.
Sources:
Cybersecurity Labeling for Consumer IoT Products
An IoT device or other digital equipment or service (e.g., backend, mobile app) used to create IoT products.
Sources:
NISTIR 8425
under IoT product component