Apple introduced HomeKit at its World Wide Developers Conference in June 2014. Apple defines HomeKit as "a framework for communicating with and controlling connected accessories in a user's home". In other words, it's Apple's platform for building "smart home" products, ensuring that compatible devices can easily be discovered, configured and managed.
This review will focus on three HomeKit certified outlets: Grid Connect's ConnectSense Smart Outlet (above left); Elgato's Eve Energy Switch & Power Meter (above top right); and Koogeek's Wi-Fi Enabled Smart Plug (above bottom right). Each switch carries the "Works with Apple HomeKit" logo (below) and provides some form of power tracking. All three also connect via Wi-Fi and require an Apple iPhone or iPad to set up and control them. I'll discuss the features of each product separately and present screenshots of the software supplied with the product.