Official support for WhatsApp on iOS 7.1.2 ended in February 2020. While you can still find legacy .ipa files for this version (such as version 2.18.81) on archival sites, it is no longer possible to verify or register a phone number on this firmware. Status of WhatsApp on iOS 7.1.2
Safety Risks: Sideloading apps from unofficial third-party sources can expose your device to malware. Potential Workarounds
The iPhone 4 is the primary device limited to iOS 7.1.2, and it is now considered obsolete by both Apple and WhatsApp.
Why Do You Need WhatsApp IPA for iOS 7/12?
