some apps require an updated iOS 10.11. But i am using a MacBook Air Early 2015. What should I do?
Should I do the update? If yes, where can I get the download?
Hi,
MacBook Air 2015 original macOS is Sierra(10.12), so you can't install El Capitan(10.11) on your MacBook Air.
If you mean update to the latest or newer macOS, you can download installers at following site.
How to get old versions of macOS - Apple Support