ine - Twitter's new video clip sharing app - has had its age rating increased to 17+ on Apple's store, the highest option. 
The software had previously been rated suitable for 12-year-olds.
It follows complaints that some of its six-second segments were pornographic.
Blogging service Tumblr and photo-sharing service 500px have also seen their iPhone and iPad apps boosted to the maximum age rating over the past fortnight.
Vine is not yet available for Android, but Google Play rates its 500px app as having a "high maturity" content rating, while Tumblr is marked as "low maturity".
Technology news site The Verge was first to note the change in Vine's status. 
The app had previously made headlines after one of its Editor's Pick showed a couple engaged in a sexual act.