Spotify might be preparing a new mobile streaming music service, according to The Wall Street Journal. That could possibly be a threat to market leader Pandora (P). To date, mobile access to Spotify's service has only been available as part of its premium subscription service, which costs a hefty $10 per month. That's much higher than Pandora's One subscription price point.

While an entree from Spotify into the free, ad-supported market poses a threat to Pandora, the incumbent has held its own remarkably well against the likes of notable tech heavyweights Apple and Google. Pandora jumped last week after it released audience metrics for November, showing a sequential gain in active users to 72.4 million. Pandora's CFO also recently outlined the company's strength in engagement and proprietary data from users voting on which songs they like or don't like.

In this segment of Tech Teardown, Erin Kennedy discusses the music-streaming space with Evan Niu, CFA, our tech and telecom bureau chief.