27 July 2021
UPDATE (July 7th, 2021):
Spotify has begun a wider rollout of offline support for Apple Watch users. The feature rollout began in May but not everyone received it at the same time. It is now reported to have expanded to cover as many users as possible from regions like the US, UK, Canada, Germany, Austria, Brazil, UAE, Italy, Ireland, Switzerland, Portugal, Malaysia, and more.
Original (May 24th, 2021)
Spotify for Apple Watch has finally received support for offline music playback. The announcement was made by the company through a blog post. It has been one of the commonly requested features since the release of the stand-alone Apple Watch in November 2018.
It was originally released as a way for controlling Spotify music playback directly from the Apple Watch. It was just last year when the team added the ability to stream music as well. However, it still needed users to either have their iPhones connected with the Apple Watch and app or to have a cellular version of the smartwatch. This made the app feel incomplete, especially considering its rival Apple Music allowed users to download songs for offline listening.
The situation has changed now as Spotify's Apple Watch app has received offline download support. The only thing to keep in mind is that this new feature is limited to Premium users. If you are one, you can go to any playlist, album, or podcast and tap the three-dot icon. It will show the "Download to Apple Watch" option for starting the download process. The app will show a green icon next to each content's name that has been downloaded.
Lastly, Spotify Apple Watch users can make use of Siri integration. They can use "Hey Siri" to trigger the assistant and help it to play favorite songs, artists, albums, playlists, and podcasts. It can also be used for controlling music playback.