Which feature allows users to control multiple smart home devices from an Apple device?

The feature that allows users to control multiple smart home devices from an Apple device is HomeKit. HomeKit is Apple's framework for smart home automation, enabling users to manage a variety of smart home products—such as lights, thermostats, locks, and cameras—through a central app called "Home." This integration allows users to create scenes and automations, making it easier to manage device interactions based on their preferences.

HomeKit is designed to enhance the connectivity and interoperability of home automation products, ensuring that they work seamlessly together within Apple's ecosystem. By using the Home app, users can easily control their smart devices, set up routines, and manage security, all from their Apple devices.

While Siri is a voice-activated assistant integrated within the Apple ecosystem that can control smart home devices, it relies on the underlying HomeKit protocol to execute those commands. Therefore, HomeKit is the foundational framework that enables this capability, making it a critical component in managing multiple devices. AirDrop and iCloud serve entirely different functions and do not relate to the control of smart home devices.