The is to open Safari on your iOS 4.2.1 device and go to mbasic.facebook.com . This stripped-down mobile site allows you to send and receive Facebook messages without the Messenger app. It’s slow, ugly, but it works.
Because the official Apple App Store currently requires much newer software (typically or higher), you cannot download Messenger directly onto an iOS 4.2.1 device. Instead, you must use archived files or specific workarounds. facebook messenger ipa for ios 421 download top
To install a legacy IPA file on iOS 4.2.1, your device must generally meet these criteria: The is to open Safari on your iOS 4