You have several options for making apps available to iOS users.
Are you using Apple’s Volume Purchase Program (VPP)? Then with help from Cortado you can distribute apps purchased there to your users. You’ll find out how to do that in the section Apple VPP apps.
For how to distribute apps from the Apple App Store, on the other hand, refer to the section Apps from the app store.
Do you use apps that were specially developed for your organization? You can also make use of Cortado to distribute those apps to your users. You will learn how to go about that in the section Own (self-developed) Apps.