Musical.ly users opened their phones to a surprise today as they found the app replaced with a new logo and name: TikTok. The app was acquired by Chinese company ByteDance in November 2017, which absorbed Musical.ly into its own TikTok app this morning. Existing Musical.ly users have been migrated over to their new TikTok accounts, which have been updated with a new interface but still retains the core feature of both apps: short-form videos up to 15 seconds.

Teen karaoke app Musical.ly, which had just reached a milestone of 100 million monthly active users, is part of ByteDance’s larger strategy to break into the US market. In the first quarter of 2018, TikTok was the world’s most downloaded iOS app, according to a report from US research firm Sensor Tower.

TikTok will remain a standalone app in China, where it operates as Douyin and boasts over 300 million monthly active users. You might have even seen Douyin clips floating around before: maybe in the form of the “Karma’s a bitch” makeover meme that went viral earlier this year, or news of Peppa Pig getting banned from the platform due to her status as a “subversive gangster icon.”

Some Musical.ly users are welcoming the changes, while others are debating how to identify themselves going forward:

musically is now “tik tok” but i will always be a muser. not a clock. — Brian (@brianbertoline) August 2, 2018

With Vine successor v2 “postponed indefinitely,” TikTok seems like the closest thing we’ll get to having Vine back. But although Musical.ly and TikTok are both platforms for sharing 15-second videos, TikTok will be missing an essential part of the Musical.ly history, which was built on teens lip-syncing and dancing to music. All the features to make karaoke videos are still there, but rebranding the app with a new name and forcing the old Musical.ly users to migrate to a new platform is a move that may alienate the original community. It’ll be up to the teens to decide whether TikTok’s popularity in China will translate to success in the US.