Fewer silly messages, fewer notifications
At the moment none of us have received the change (it shouldn’t even involve the update of WhatsApp on iOS, it is probably a web-based change), but in the Android screenshots that you can see above it is verified how the operation is very easy: keep your finger pressed on a message and choose the reaction. No more. If you use Telegram, iMessage or Facebook Messenger, it is something you have been doing for a long time.
This is a good way to save messages and notifications to messages that only need a very simple response. Remember, the emojis you can use are the following: 👍❤️😂😲😥🙏
If you still do not have the news, be patient: Zuckerberg has confirmed that it will be deployed from today but it may take days to see it active on all iPhones. Just in case, you can check if there are any available WhatsApp updates on the App Store and download them manually.