BEIJING (PingWest) — Amazon says its music service users has now topped 55 million, becoming a threat to two music streaming giants Apple and Spotify.

Apple Music now has 60 million users and Spolify reported 113 million users back in September.

The rapid growth is largely because of the popularity of Amazon’s Prime membership that Prime subscribers have free access to over 2 million songs, and the integration to Amazon’s Alexa voice assistant.