Music on Vine - Vine, now with music. Make 6-second music videos.
Bandlab - Capture, nurture, and collaborate on song ideas in the cloud
Mindie - 10 second music videos (w/ private mindies)
Amper Music - Artificial intelligence music composer
Triller - Make celebrity-quality videos with a few taps of your phone
Storybeat - Storybeat app comes up with features to help you in changing the background music of your videos in a few simple steps to share your favorite moments with your social media friends.