BlackBerry Messenger, the service that introduced the concept of mobile chat, is shutting down after a decline in popularity.
Also known as BBM, it was once the crown jewel of BlackBerry's phone service and during its heyday played a pivotal role in the 2011 London riots owing to the encrypted nature of the messages.
BlackBerry Messenger was initially very popular when it first launched on the company's own devices in 2005.
However, the arrival of the iPhone and Android smartphones gradually dented BlackBerry's popularity.
Many users started using WhatsApp and other messaging platforms that were not stuck to BlackBerry.
BBM was broadened to Android and iOS in 2013 but it was not enough to ensure its survival.
The Indonesian company that owns the consumer service, announced its plans in April, giving users a month to switch.
A paid-for business version called BBMe will continue to exist.
BBM owner Emtek, which took over the app from BlackBerry in 2016, said last month: ''We poured our hearts into making this a reality, and we are proud of what we have built to date.
"The technology industry, however, is very fluid, and, in spite of our substantial efforts, users have moved on to other platforms, while new users proved difficult to sign on.
"Though we are sad to say goodbye, the time has come to sunset the BBM consumer service, and for us to move on."
A spotlight was thrown on BBM during the summer London riots of 2011.
The Metropolitan police highlighted that the encrypted nature of the messages meant they could not eavesdrop on communications, as they could with older SMS texts.
It was also pointed out BBM made it much easier to send one-to-many broadcasts than most phones at the time.
BBM has also been linked to crime rings.
In 2017, it was reported Dutch police managed to crack data held on a private server protected by end-to-end encryption.
It was part of an investigation into the alleged sale of BlackBerry devices linked to multiple crime rings involved in assassinations, armed robbery, drug trafficking, and money laundering.