Keep an old iPhone or iPod touch for the exclusive apps. This is the only reliable, non-malicious method.

An is the archive file format used by Apple for iOS, iPadOS, and ARM-based macOS apps.

: IPA files from the App Store are encrypted with Apple's DRM, meaning they must be decrypted on a jailbroken iOS device before they can even be looked at by other tools. No Direct "Installer"