The Good: Twitter Music has a beautiful interface for discovering music that's popular on the social networking service. You also can see which other artists like your favorite music, to potentially find new favorites. The Bad: You need to sign up for a subscription with Rdio or Spotify to hear full-length songs. The search function is limited to finding artist profiles. The Bottom Line: Twitter Music is a great way to see which music is generating interest on Twitter, but don't count on it to replace your current music player. Just over a month after the app's existence by CNET, Twitter Music has . As promised, it provides a way for you to discover tunes through artists and songs trending on Twitter, check out the artists who follow your favorite bands, and listen to and purchase music directly.\n\nSounds simple, right? Well, the reality is a bit more complex. First off, the app is a more of a music discovery tool rather than a music player. You won't be able to search for and play specific songs or create radio stations as other services do; rather, this app is more about finding music that people are talking about on Twitter. Is it useful to know what's the most popular song on Twitter? I'm not so sure. People follow artists and other users on Twitter for a lot of different reasons. You may follow an artist because you like her music or you because he's a fascinating social-media personality. Twitter Music won't know the difference. \n\nWhat's inside\nYou can get to the main navigation area of the app with a button at the top, where you'll find selections for Popular, Emerging, Suggested, and NowPlaying. The Popular section shows you what's currently trending; Emerging gives up-and-coming acts; Suggested shows you artists you might like based on your tweets and follows; and NowPlaying shows the songs that people you follow have mentioned recently. The interface is very well laid out for what the app does, with colorful pictures of artists that are fun to browse. But the thing I can't get past is that each of these lists is based on the Twitter world alone. I can get top 40 lists anywhere, so why would I want to get them just from Twitter users? Frankly, I couldn't quite think of a reason. \n\n\n\nThere is also a search function, but in my testing, it seemed only to be useful for looking up artist profiles. I did a few searches for popular songs, but got limited results.