Outside the EU, however, Apple still does not officially permit unrestricted sideloading. Apple argues that its prohibition is “integral to ensuring that all apps loaded on iOS meet Apple’s quality and safety standards.”
An IPA (iOS App Store Package) is the executable file format used for Apple iOS applications. A Messenger IPA contains the binary code, assets (like icons and images), and configuration files specifically for the Facebook Messenger app on iPhone and iPad. Common Uses for the IPA messenger ipa file