The betas of iOS 16.1 and iPadOS 16.1, released to developers on Wednesday evening, add a new "Matter Accessories" section to the Settings app. With this, Apple is preparing for the introduction of the new smart home standard Matter.
Tapping the Matter Accessories section under General will display all Matter accessories that are part of a connected service added The description states:
These can also be added to additional services using an app that supports Matter.
Apple has not yet implemented official support for Matter, but has said it will roll out sometime this fall—possibly with iOS 16.1.

iOS 16.1 could introduce Matter
Matter is a new interoperable, secure connectivity standard designed for smart home devices. Matter was developed by the Connectivity Standards Alliance, which includes technology companies such as Apple, Amazon and Google. This ensures interoperability between smart home devices from different companies. So HomeKit, Google Assistant, Alexa, SmartThings and other smart home devices that support Matter will be able to work together. Some accessory manufacturers will support Matter once the new standard is released and supported by Apple. (Photo by DenPhoto / Bigstockphoto)