Apple Arcade is currently available for devices with iOS 13, iPadOS 13, macOS Catalina, and tvOS 13 installed.
You can try out the service with a one-month free trial. After that, Apple Arcade is $4.99 per month.
A subscription can be shared with up to six other members of your family with Family Sharing.
To subscribe on your iPhone or iPad, open up the App Store tab and then select the Arcade tab.
Select the Try it Free button on the top of the page.