Spotify finally caved to the pressure last week and introduced its own ad-supported free streaming feature for mobile users. The smartphone version is restricted to Shuffle Play and artist/album radio stations, but that hasn’t stopped users from downloading Spotify in droves. According to CNET, Spotify saw four times the number of downloads since the feature launched last week. The company hasn’t released any official numbers yet, but there’s little doubt that free streaming would fail to draw a crowd. Spotify also climbed into the top 10 in the App Store in 20 markets, including the U.S. after the rollout. There’s still plenty of catching up to do before Spotify can overtake Pandora, but it’s certainly on the right track.