This feature is available in iPhone only which allow users to add date as event in their calendar. If your friend sent you a date within message, it will have a blue underline in it. Just long press the date and option appear to create event in your calendar for that date.
Disclaimer: These were all the WhatsApp Tips, Tricks, Tweaks, Hacks and Secrets that we have found till now. If you know any other interesting trick, please share it in the comments section below. All the WhatsApp Tips and Tricks we are providing through this article are for educational purpose only. Neither we nor WhatsApp (or any other app/service) will be responsible for any inappropriate use of these tricks.
If you're planning to become one of the smartest WhatsApp users, you can achieve that by learning all the tricks provided here in detail.
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