SYNC AND SEND SONGS AND MUSIC TRACKS
The Samsung Galaxy Watch 4 lets you transfer a bunch of offline tracks from your smartphone to your smartwatch. So that when the time comes, you can connect your wireless earbuds directly to the watch and listen to your favorite tracks.
To do so, head over to the Manage Content tab and select Add tracks. Once done, select the tracks and hit the Done button.
Source : guidingtech.com