Apple is working on a new smart home accessory that will serve as a hub for interacting with Siri AI, controlling HomeKit devices, watching videos, checking the calendar and the weather, and generally offering up useful information to everyone in the household. This guide aggregates everything that we know about Apple's smart home hub. Design Apple's smart home device will somewhat resemble an iPad , and it will have a display-focused design. It is expected to be square rather than rectangular, and it will measure in at 6 inches with quarter-inch black bezels around the edges. In terms of…