If you are absolutely determined to try and salvage your WhatsApp chat history from an iPhone 4s or similar device, there is one last, desperate measure you can take. It requires a lot of time and effort and is not guaranteed to succeed.
The most significant danger of downloading an IPA from unofficial sources is security. WhatsApp is a primary vector for personal communication—messages, photos, videos, contacts, and even payment details in some regions. An IPA file obtained from a forum, file-sharing site, or a "tweak store" can be modified to include spyware, keyloggers, or ransomware. Since iOS 9.3.5 has not received a security update since 2018 (aside from the rare critical patch like the Pegasus exploit fix), any sideloaded app would operate on a deeply vulnerable operating system. In other words, by seeking a working WhatsApp IPA, a user might be handing over the keys to their entire digital life to an unknown third party. whatsapp ipa for ios 9.3.5 download
This method uses your computer to sign the WhatsApp IPA file with your Apple ID and install it onto your iOS 9.3.5 device. If you are absolutely determined to try and