So, basically, f you're using a phone with Android 2.3.7 (Gingerbread) or iPhone using iOS 7, it's time to make the upgrade to a newer phone.
WhatsApp's updated FAQs said on Tuesday that users whose devices have those operating systems "can no longer create new accounts, nor reverify existing accounts" after that date.
The company said it expected a limited impact from the change since it would only affect users who had not purchased a new phone or updated their operating system in more than six years.
In fact, users whose devices have older operating systems are already unable to create new WhatsApp accounts or reverify existing accounts, but the company does allow those who already have the app on their phones to continue using it.
This change is expected to have even less of an effect on users since only about 0.24 percent of mobile phones around the world, according to Statcounter, use a Windows operating system.
This figure includes all versions of the Windows operating system, including the more recent Windows 10 Mobile, which means the number of current Windows Phone users is insignificant.
WhatsApp recommends using the with Android 4.0.3 or later, and for iPhone users, t needs to be iOS 8 or later. Jio phone and Jio phone 2 users can continue using the app on their 4G-enabled feature phone.