Source: http://lifehacker.com/5802110/boxytunes-turns-dropbox-into-a-cloud-music-player-for-iphone-and-ipad
What Does It Do?
BoxyTunes syncs up with your Dropbox account and lets you download music stored inside for playback on your iPhone or iPad. Is that it? Yeah, pretty much. It does play every format iOS supports, works in the background, has AirPlay support, and has a quick rewind button for replaying the song you're listening to if you decide you want to hear it again (I think this button was made for me). What does it not do? Multiple playlists, which solidifies its position as a secondary music player. It's not going to replace the iPod app.
Who's It For?
Yes, it has a small feature set, but what it does do is excellent if you're looking to play music stored in your Dropbox. This app is for people who don't have the music they want right now on their iDevice. Maybe you don't sync everything to your device or maybe you just forgot to sync it, but if it's not there you can use BoxyTunes to easily grab it from the cloud.
Worth It?
BoxyTunes isn't perfect, but it's also only $2. While you can use the free Dropbox app to download and play your music on the go, and BoxyTunes doesn't provide much in the way of features, it works a lot better. If you sync your music with Dropbox and ever want to play it on the go, then it's absolutely worth it.
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