Kik Messenger is shutting down despite the service having millions of active users around the world.
The company said it was closing down the messaging service so it could concentrate on the Kin cryptocurrency it has also created.
In a blog, Kik Interactive said the decision had been forced on it by a legal wrangle with the US Securities and Exchange Commission (SEC) over Kin.
The decision also means that 80 staff who keep Kik running will be let go.
No date has been given for when the Kik app will close.
Kik Messenger launched in 2010 and proved popular largely because it lets people register and use it without providing a phone number or other credentials.
The app has also proved controversial and a BBC News investigation in 2018 suggested it had featured in 1,100 UK child sexual abuse cases police had investigated in the past five years.
In response, Kik said it was â€œconstantly assessing and improving its trust and safety measuresâ€.