I have an HTC One (M7) and use Remote for iTunes (Google Play Store). Works WAAAYYY better than the Apple remote app on iOS - no kidding, it's more responsive and doesn't disconnect you from the remote iTunes when the screen goes to sleep, which is really annoying with the Apple version.
Just be aware that this only works for Audirvana in iTunes integration mode, but this combination is my most used digital source and it's very robust with my headless Mac Mini.
Thanks. I'll be sure to get that app.