If you still wish to attempt the download, there are two types of sources. Neither is endorsed, and both carry significant risks.
WhatsApp’s backend protocols have changed dramatically since 2015. The old WhatsApp clients (versions 2.11.x and 2.12.x) use obsolete encryption handshakes. When you try to verify your number, WhatsApp’s server will reject the connection. You will see the infamous error: “You need to update WhatsApp to the latest version to continue.” Ios 4.2.1 Whatsapp Ipa Download
No official version works anymore.
WhatsApp officially dropped support for iOS 4.x back in 2016. The last compatible version was WhatsApp 2.12.x. Even if you find an old IPA file, WhatsApp’s servers will reject the connection because the security certificates and API requirements are outdated. If you still wish to attempt the download,