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Yes, your phone can be dead and the watch can play music that's stored on it. Force touch in the music app to change the source to Apple Watch instead of iPhone.
 
It works and I love it. The only caveat is that you need to have your watch on the charger before any music is transferred from your phone. Your best bet is check out the manual to get clearer instructions.

2 quick tips.

when you first get into the music app on the watch, press on the watch to get the submenu to show up, select source, and select your watch.

In the now playing screen, press on the display to bring up the submenu, select airplay, then your bluetooth headset.

Then your good to go.
 
It works and I love it. The only caveat is that you need to have your watch on the charger before any music is transferred from your phone. Your best bet is check out the manual to get clearer instructions.

2 quick tips.

when you first get into the music app on the watch, press on the watch to get the submenu to show up, select source, and select your watch.

In the now playing screen, press on the display to bring up the submenu, select airplay, then your bluetooth headset.

Then your good to go.

Thanks all!
 
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