Use (discontinued but still connects) or simply use Facebook’s mobile site with desktop mode for messages.
Older versions may give a "Connection Error" during login. This is often because Facebook's modern security protocols (SSL/TLS) are too advanced for iOS 9's outdated Safari engine. facebook+ipa+for+ios+935+best
Avoid unknown “IPA signing sites” (like iOSNinja or PandaHelper for this specific old version). They often inject ads that crash iOS 9.3.5 instantly. Use (discontinued but still connects) or simply use
Connect your device to a computer and use Sideloadly to drag and drop your Facebook IPA. facebook+ipa+for+ios+935+best