Review: Samsung Gravity Smart
The Gravity Smart uses the same, drab, boring music player that's on nearly all Android devices. Samsung did nothing to make it fun to use. Side-load your music via a PC and the microUSB port (or directly onto the microSD card itself) and the Gravity Smart will find your tunes and play them back with no problem.
If you want more than simple playback, you'll have to jump into the Android Market, where hundreds of apps (including Amazon MP3 Player, Pandora, Slacker, among others) are available for download.
The Gravity Smart makes use of the stock YouTube app to satiate video snacking needs. It's a good piece of software for browsing through videos on YouTube and playing them back. The photo gallery software is used to play back any video content captured on the device itself or side-loaded to the microSD card. It is a bare-bones player, but it works.