Developed by Maxim Rabiciuc, ‘Watchify’ is a new Spotify client for the Apple Watch offering a simple UI, a decent set of features, and is available as a free download in the App Store. However, in order to use the Watchify app, users need to have a Spotify premium account.
Watchify has been built using the Spotify iOS SDK and lets users chose from their Spotify songs and playlists using their Apple Watch and play them from their iPhone. The app lets you pause, play, skip, and replay songs just like the official Spotify app.
You can grab the Watchify app for Apple Watch using this App Store link.