200,000 downloads in 20 days. That’s how brisk business has been for Rhapsody since Apple approved its streaming music iPhone app.

Not that there haven’t been kinks. RealNetworks (NSDQ: RNWK) has an upgrade that will fix “a few stability bugs” ready for release, and another upgrade for enhanced audio quality coming later this month.

The company also said it had been testing Rhapsody on Android, it’s next app, with a launch slated “before the end of the year.” A preview of the app on the myTouch is here.

• Apple Approves Real’s Rhapsody iPhone App; First Look