If a version for iOS 4 exists in the archives, you will see a prompt: "Download an older version of this app?" . 2. Sideloading via Jailbreak (Requires AppSync)

Current versions of the Facebook app require iOS 13.4 or higher. Methods for Installing Legacy Apps

Because the native app often fails to connect to modern servers, the most reliable way to access Facebook Messenger on iOS 4.2.1 is through the . Navigate to: m.facebook.com

For users seeking a Facebook Messenger IPA for iOS 4.2.1, here is the reality of current compatibility and the available workarounds.