This is because Apple has since released Swift Playgrounds 4, an app for the iPad and Mac. With this latest version of Swift Playgrounds, users will now be able to design and create their apps using their iPads and submit them to Apple directly from the tablet itself, instead of having to use their Mac computers to do so.
This is pretty handy for developers who might constantly have their iPads with them versus a MacBook Air or MacBook Pro, or for developers who have their iPads on them and want to do a bit of coding instead of having to wait to go home and get on their Mac computers.
Swift Playgrounds 4 was initially announced at WWDC 2021 earlier this year, but was ultimately delayed until now. For developers who are interested in checking out the app, you will be able to download the latest version from the App Store. Keep in mind that you will need to have an iPad that has iPadOS 15.2 or later, so if you own a particularly old iPad that doesn’t support the latest iOS update, then you’re out of luck.