WhatsApp dropped support for a number of mobile phone platforms on December 31 2017.

The Facebook-owned app previously said support for BlackBerry OS, BlackBerry 10, Windows Phone 8.0 and older devices would stop at the end of 2017.

However, as 2018 has kicked into gear users of BlackBerry 10 devices may have found that WhatsApp is still working on their smartphones.

And in a boost to BlackBerry 10 users, WhatsApp confirmed the chat app will continue working on these devices - for the time being.

In a statement to CrackBerry, WhatsApp said BlackBerry 10 fans will get to use the app for around two weeks before support eventually ends.

They said: “[WhatsApp] will still continue to function for a short grace period, but some behaviours will change. Most importantly, you will no longer be able to re-register your account with the app. 

“That means if you delete and reinstall it (or install it on a different phone), it will no longer allow you to verify your phone number and complete the setup process. 

“After the grace period, which is approximately two weeks, the app will go into 'expired' mode.

“At this point, it will stop functioning as a usable WhatsApp client, and thus will no longer connect to our servers. (Around this same time, our servers will stop allowing the client to connect as well.) 

“However, once it is expired, the BlackBerry 10 client app may still allow you to access your existing message content on your phone. 

“This behaviour should be similar to what was seen by everyone who forgot to update their app the last time our published expiration date had passed.”

It was originally announced that WhatsApp support for BlackBerry OS, BlackBerry 10 and Windows Phone 8.0 would stop at the end of 2016.

But this was later extended to the middle of last year, before being pushed back again to December 31 2017.

Fans of the BlackBerry KEYone and BlackBerry Motion needn’t worry as their devices will continue to get WhatsApp support.

In a previous blog post, WhatsApp explained why they were ending support for BlackBerry OS, BlackBerry 10 and Windows Phone 8.0 devices.

They said: “While these mobile devices have been an important part of our story, they don't offer the kind of capabilities we need to expand our app's features in the future.

“This was a tough decision for us to make, but the right one in order to give people better ways to keep in touch with friends, family, and loved ones using WhatsApp.”

They also added: “Because we will no longer actively develop for these platforms, some features may stop functioning at any time.”

WhatsApp also confirmed support for the Nokia S40 will stop after December 31 2018.

While Android versions 2.3.7 and older while finish after February 1 2020.

The news comes after WhatsApp rolled-out the ability to delete sent messages.

WhatsApp users will be able to delete messages that they have either sent to a group or an individual chat.

Messages that have been successfully deleted in a chat will be replaced by “this message was deleted”.

There is one catch though - WhatsApp users are only able to delete messages within seven minutes of sending it.

The WhatsApp team said: “Deleting messages for everyone allows you to delete specific messages you have sent to either a group or an individual chat. 

“This is particularly useful if you sent a message to the wrong chat or if the message you sent contains a mistake.

“Messages you successfully delete for everyone will be replaced with "This message was deleted" in your recipients' chats. 

“Similarly, if you see ‘This message was deleted’ in a chat, it means that the sender deleted their message for everyone.”