TikTok has announced a series of changes it says are designed to protect its teenage users' wellbeing.
Users aged 13-15 will not receive push notifications from 21:00 - and for 16- and 17-year-olds, from 22:00.
This is to help them focus on work, study, relaxation and sleep, the video-sharing app says.
It is also changing its default settings so 16- and 17-year-olds will have to opt in to receive direct messages.
TikTok on Thursday announced stricter privacy controls for teenagers, seeking to address criticism that it has failed to protect children from hidden advertising and inappropriate content.
Owned by ByteDance, TikTok has grown rapidly around the world, particularly among teenagers. However a number of incidents have prompted concerns about its privacy and safety policies.
A pop-up will appear asking teenagers under the age of 16 to choose who can watch their videos before they can post them.
"The process of making a TikTok is fun and creative – choosing music, picking effects, and getting the transitions right – but it is just as important to choose who that video will be shared with," TikTok's head of child safety public policy, Alexandra Evans, and its global head of privacy, Aruna Sharma, said in a blogpost.