The primary hurdle is that Facebook’s server-side protocols have changed drastically since iOS 4 was current.
your device (e.g., using GreenPois0n or Redsn0w for iOS 4.2.1). facebook messenger ipa for ios 4.2.1 download
Use a newer device or iTunes on a computer to "buy" (download) Messenger on your Apple ID. Step 2: Open the App Store on your iOS 4.2.1 device. Step 3: Go to "Purchased" and try to download Messenger. facebook messenger ipa for ios 4.2.1 download
For users seeking a Facebook Messenger IPA for iOS 4.2.1, here is the reality of current compatibility and the available workarounds. facebook messenger ipa for ios 4.2.1 download