Faced with slow growth in new users and usage by existing users, Twitter executives repeatedly promised improvements to make the social network more inviting.

On Tuesday, the company delivered on two of those promises, adding the ability to send a private message to a group as well as adding a video recorder that allows users to shoot, edit and post video directly from Twitter’s mobile apps. (Last week, the company fulfilled another promise, adding a feature for iOS users called Recap that shows top tweets that you missed since your last login.)

While hardly groundbreaking, the video and messaging features finally bring Twitter on par with Facebook, its much larger rival, which has offered group messaging and integrated video for some time. Perhaps more important for Twitter’s investors, the improvements show that the company, which was notorious for the creeping pace of its product improvements, is picking up the tempo under the new leadership installed by Dick Costolo, its chief executive, in a series of management shake-ups last year.

The group messaging service allows Twitter users to send a private message to up to 20 people, either predefined as a group or created on the fly. While any kind of message can be sent — and probably will — the feature is geared toward sharing and discussing a tweet. To keep down spam, you will initially be able to send a message only to people you are already connected with on the service. But other people in the group can add their contacts, allowing a larger conversation to occur.

The video software is aimed at capturing live events and sharing them with the public. From the box where you post tweets, you will be able to touch a camera icon to fire up the software, which allows you to shoot and combine snippets of video into a clip of up to 30 seconds.

“Anyone on Twitter will be able to capture and share video,” said Jinen Kamdar, a Twitter product director, said in an interview to discuss the changes. “It’s less about pro editing and more about getting authentic clips out in the world really quickly.” The videos can be played with one click.

Video is the biggest battleground among social and media sites, with giants like Facebook and Google’s YouTube vying with smaller sites to keep the attention of visitors — and show them more advertising while they’re there.

Twitter’s new video product could increase traffic and the amount of time that current users spend on the service, and better messaging could keep them from turning to pure messaging apps like WhatsApp and Snapchat to pass along the latest cool link or photo. (An expected new feature to lure new users, an instant feed of content to follow as soon as someone signs up, is due within weeks.)

The company is adding the new messaging and video features to Twitter.com as well as the latest versions of its iOS, Android and TweetDeck apps released Tuesday. But the messaging and video updates won’t actually be available to all 284 million active users right away — the company is gradually activating them for its entire customer base over the next couple of weeks.

Mr. Kamdar said that unlike many new Twitter features, these were tested only internally among Twitter employees before going live. So the company will be just as curious as Twitter users to see how they are used in real life.

New York Times