The External Accessory Framework facilitates communication between iOS devices and MFi (Made for iPhone/iPad) certified external accessories like hardware devices and sensors, ensuring compatibility, security, and reliability through Apple’s authentication chip. The External Accessory Framework lists connected EAAccessory devices and uses NotificationCenter for events like EAAccessoryDidConnect and EAAccessoryDidDisconnect to monitor connections. EASessions, filtered by communication protocols, enable data transfer through input and output streams for interacting with these devices.