One plus 3T - Manual (Page 21)

21 | What’s in the Box Device OxygenOS Safety Information
OnePlus Music
A brand-new home-baked music player optimized for offline use is also available out of the box. With a simple and straight-forward design,
OnePlus Music provides you with just what you need. Use tags to organize and build up your music library without having to play around
with files & directories.
| What’s in the Box Device OxygenOS Safety Information