There's no need for a separate gaming controller for your iPhone or iPad if you've got a Nintendo Switch.
https://www.cnet.com/tech/mobile/heres-how-to-use-your-nintendo-switch-joy-cons-to-play-games-on-your-ipad-and-iphone/?utm_source=dlvr.it&utm_medium=blogger#ftag=CAD590a51e
https://www.cnet.com/tech/mobile/heres-how-to-use-your-nintendo-switch-joy-cons-to-play-games-on-your-ipad-and-iphone/?utm_source=dlvr.it&utm_medium=blogger#ftag=CAD590a51e