The BlackJack II's Windows Media Player does provide the ability to play MP3's, whether previously downloaded to either the phone memory or a microSD™ memory card. Tip: Audio files less than 300 KB are treated as ringtones, whereas audio files which are greater than 300 KB are considered as Music. A user cannot set an MP3 file as a ringtone if it is larger than 300 KB. Please Note: Windows Media Player does not necessarily support all features of a particular file format nor all the variations of those formats. Windows Media Player includes support for Digital rights Management (DRM) which allows you to play some purchased or subscription content. Copyright protections may prevent some images, videos, music (including ringtones) and other content from being copied, modified, transferred or forwarded. Note: The SGH-I617 (BlackJack II) media player supports files with extensions AAC, AAC+, MP3, MIDI, WMA, 3GP, MPEG, MP4, and M4A.