CNN has acquired video-sharing startup Beme, a social media app launched last year by popular YouTube star Casey Neistat, the cable-news network announced Monday.

While the deal will bring the app’s video technology to CNN, it will also allow the news company to tap into Mr. Neistat’s large, young digital audience. The deal is valued at about $25 million, according to people familiar with the matter.

As part of the acquisition, CNN will by summer of next year launch a standalone media company led by Mr. Neistat and Beme co-founder Matt Hackett that will focus on “timely and topical video and empowering content creators to use technology to find their voice,” CNN said in a statement.

The Beme app, which allowed users to shoot and share quick, unedited video clips, had an auspicious start thanks in large part to Mr. Neistat’s diehard social media following. But the service struggled to grow and compete with apps like Snapchat and Instagram.

The Beme app will be shuttered, with the company’s 11 employees joining CNN to form a separate technology unit focusing on the new media venture and CNN’s wider mobile video efforts.

Mr. Neistat will retain control of his personal social media channels and accounts, such as his 5.8-million subscriber strong YouTube channel. CNN said that while the acquisition was not a TV talent deal, the company is exploring ways for Mr. Neistat to connect with new audiences.

Write to Steven Perlberg at steven.perlberg@wsj.com