Ios Update. If the update doesn't appear on your device, use your computer to update your device manually. To use Apple Pay Later, you must have an iPhone or iPad updated to the latest version of iOS or iPadOS.
Learn how to update the software on your iPhone, iPad, or iPod touch. Learn how to update your device manually if you're using a Mac with macOS Catalina or later, or if you're using a Mac with macOS Mojave or earlier or a Windows PC. To use Apple Pay Later, you must have an iPhone or iPad updated to the latest version of iOS or iPadOS.
Plug your device into a power source and connect to the internet with Wi-Fi.
Here's what's in the latest update.
If you don't see your device, learn what to do. Update to the latest version by going to Settings > General > Software Update. Go to Settings > General, then tap Software Update.