Update: Grooveshark has been pulled from the Android Market. You can read the full story here.
Listening to music is one of the main things people like to do with their Android phones, but getting music onto the device and managing playlists can be a hassle. Through the Grooveshark Web-based service, you can find, discover, and stream just the music you want to your phone. You can build, save, and share playlists, and save local copies of songs on your phone's SD Card. Offering a large catalog of music, Grooveshark is free for 30 days, after which it costs $3 a month or $30 a year.
Grooveshark is purely a streaming service; it does not play MP3 files stored on your phone. To use Grooveshark, you must first create an account: Simply provide your e-mail address plus a username and password, and you're ready to start streaming music. In the app you can search by artist, album, song title, genre, and playlist. You can also browse other users' playlists--a nice way to discover new music. Album art usually, but not always, displays with the music.
Once you choose a song, you can add it to your Favorites, add it to a new or existing playlist, or save a local copy on your phone. The last option comes in handy for areas where you can't get a good data connection.
Locally saved songs store not as MP3s but as files with a .data extension. It would be nice to save them as MP3s so that other media players could play them as well, but that is not an option at present.
You can share links to Grooveshark-hosted songs and playlists via e-mail or Twitter. In my tests, sharing these on Facebook resulted in an error, but I'm not sure if that was a problem with Grooveshark or with Facebook. You can also access your Favorites and playlists through a desktop Web browser and through the Grooveshark iPhone app.
Sound quality depends on the bit rate (the amount of data being streamed per second). By default Grooveshark chooses a low bit rate, which is better for situations with a poor data connection but sacrifices some sound quality. In the Settings menu, you can choose whether the app should stream low-bit-rate or high-bit-rate music. I chose the high-bit-rate setting.
Sometimes when you try to play a song, the player returns an 'unknown error' message. When this happened, I found that if I just pressed the Play button again, the song would play.
Grooveshark can also play music in the background while you are using another app, or when the phone touchscreen is turned off. To return to Grooveshark, simply swipe the notification area and click the icon.
The app also claims to feature Pandora Radio-style stations, customized to the theme of your current song selection. Unfortunately, this feature did not work on my device, a Sprint EVO 4G running Android 2.2. This would be a nice way to discover new music, if it worked.
If you want a media player that will play the MP3 files you already have, Grooveshark is not for you. But if you like to stream music on demand, on multiple devices, and without having to worry about where to store the files, Grooveshark is a good choice. Just $3 a month or $30 a year is a reasonable price for access to thousands of songs and the ability to play them whenever you wish.
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