WhatsApp is an app that never released on the PS4 sometime around 2013 to 2015. It appears to be a port of the mobile app of the same name. No copies have resurfaced and we only have one picture confirming its existence.
The image though, is fake, as the WhatsApp logo lacks any texture and the text on the bottom isn't clear enough, even though the rating is. It also wouldn't make sense for WhatsApp to be sold on physical media, and would've instead been released for free as a digital app on the PlayStation Store.
While other mobile apps have been released on the PS4 such as YouTube, WhatsApp may be unreleased due to it being a messaging app, which means it relies on a keyboard for it's features, and would be a hassle for Dualshock users.
Updates
Someone found a Brazilian thread on Bungie from 2015 where they talk about the app, probably another person on the same thread in 2024, when the official PS4 version released.
I remeber seeing a YouTube video with 1 view about this app but I can't find its link. (He probably didn't, and he had a stray memory.)