Microsoft announced the new additions to its range of officially sanctioned third-party Xbox peripherals in a post on Xbox Wire. The first two Designed for Xbox iOS controller devices are the Backbone One for Xbox and the Razer Kishi Universal Gaming Controller for iOS, both of which retail for $99 and come with a complimentary three-month trial membership for Xbox Game Pass Ultimate, which you'll need to play Xbox Cloud Gaming on your platform of choice (it's also available on PC via browser and Android via app).
Both controllers feature an expandable clamp design that secures onto either side of your phone in landscape mode. The Backbone One is designed to plug directly into your phone and run off of its battery, requiring no charging of its own, and it also links up with a dedicated Backbone app which will help with capturing and tagging gameplay as well as navigating between Cloud Gaming and other iOS games and services.
The Razer Kishi Universal Gaming Controller for iOS includes a battery of its own that can charge your phone for extra battery life (which could become important sooner than you expect, since streaming all that video takes its toll on your battery). We reviewed a previous version of the Razer Kishi last year and found it to be a huge upgrade for mobile gaming with great thumbsticks and no detectable input latency, and it looks like this latest iteration will do the same.
Meanwhile, if you're more interested in playing at home, Microsoft is also expanding its Designed for Xbox lineup to include a selection of monitors which are purpose-built to make the best of your Xbox Series X's visuals. Or if your Xbox gaming machine happens to be a PC like mine is, you could peruse our selection of the best HDMI cables for gaming and see if you can get hooked up that way.
And if you're just trying to get your hands on a console, stay plugged into our guide to finding Xbox Series X stock.