Twitter to remove 140-character limit in direct messages

Twitter announced on Thursday it was dropping the 140-character limit for direct messages — but not for tweets — starting July, which will bring it right into the middle of a messaging war.

In an unconnected announcement a few hours later, the company said its CEO Dick Costolo was stepping down, to be replaced temporarily by co-founder Jack Dorsey.

Twitter has been tweaking direct messaging (texting) service, positioning it to take on rival services by Facebook, Google, BlackBerry and Yahoo.

"We've done a lot to improve direct messages over the past year and have much more exciting work on the horizon," said Sachin Agarwal, who heads direct messages, in a post. "One change coming in July that we want to make you aware of now (and first!) is the removal of the 140 character limit in direct messages."

Twitter has 302 million monthly active users world wide compared to Facebook's 1.44 billion. Its monthly growth is down to 14% this year from 30% two years ago.

It also trails Facebook and Google in share of the mobile ad market in the US.

Sluggish growth had brought the company and its CEO Costolo under scrutiny and criticism in recent times, with many calling for changes at the top.

Dorsey, who heads payment services company Square, will replace Costolo temporarily till a full-time replacement is found by a search committee of which, notably, he is not a member.