Have you seen a working proof-of-concept? Share your findings in the community forums.
There were also other community projects, such as using a local web server or a Plex server to stream content through the 3DS's browser. In 2016, some even managed to get the Spotify web player to partially load, but no audio would play through the speakers. spotify 3ds homebrew
Homebrew applications created by independent developers that connect to your Spotify account using official developer tokens to stream audio. Have you seen a working proof-of-concept
With these resources and a little patience, you can unlock the power of Spotify on your 3DS and take your music library with you wherever you go. spotify 3ds homebrew
