The basic idea is that you can only use Music Maniac - MP3 Downloader to download free songs - in other words, songs that you don't have to purchase. However, these databases are freely accessible and 'sometimes' you can find and download some very popular for-purchase songs.
Music Maniac - MP3 Downloader is a relatively interesting tool for music fans, as it allows them to download thousands of songs for free, just by searching for the name of the artist or the song. In addition, in general the quality of the MP3s is usually quite good.
Requires Android 2.2 or later.