Use Sideloadly or an older version of iTunes (12.6.5) to move the file. ⚠️ Important Limitations
Installing Viber on (common on the iPhone 3G and 2nd Gen iPod Touch) is no longer officially supported and is quite difficult in 2026. The current App Store version requires much newer software, and official support for iOS 4 ended over a decade ago. Apple Support Community Performance & Compatibility Review Official Incompatibility Viber .ipa for ios 4.2.1
iOS 4.2.1 has excellent jailbreak tools (greenpois0n, redsn0w). Jailbreaking allows you to bypass signature checks and install any .ipa using tools like iFunBox or iPhone Explorer . Use Sideloadly or an older version of iTunes (12
Viber does not officially support legacy firmware like iOS 4.2.1. The official App Store will generally only offer the "last compatible version" if you have previously "purchased" (downloaded) Viber on your Apple ID.
az
