On Monday of this week, Apollo - the default music player in Cyanogenmod - was released to the Play Store in both free and paid variants. As of yesterday, just four days after its release, both versions of the app have been pulled due to alleged copyright infringement.
Andrew Neal, the app's creator, took to his Google+ page to let users know what happened:
Hey, just to let those of you who noticed that Apollo and Apollo+ are no longer in the Play Store know, MusixMatch filed a complaint and had them removed for alleged copyright infringement due to the way that Apollo fetches lyrics. I'm looking into the best way to handle this, and will be trying to get Apollo back into the store ASAP. That's all I know for now.
Unfortunately, that's all the information we have at this time. As stated above, Andrew is trying to find a quick and efficient way to correct this issue - but Google doesn't normally take accusations of copyright infringement in the Play Store very lightly, so it could be a few weeks before we actually see Apollo and Apollo+ become available again.
We'll keep you posted of any new information as it arises.