now there's a Music & Movie Player for Apple Watch named "MMPlayer"
(1)storage files on your watch,you can delete files on your iPhone
(2) play music or movie full screen on your watch
(3) play music by bluetooth background
app store link:
https://itunes.apple.com/us/app/mmplayer-for-watch-shou-biao/id1050452971?l=zh&ls=1&mt=8
(1)storage files on your watch,you can delete files on your iPhone
(2) play music or movie full screen on your watch
(3) play music by bluetooth background
app store link:
https://itunes.apple.com/us/app/mmplayer-for-watch-shou-biao/id1050452971?l=zh&ls=1&mt=8