Is it more or less than that same mp3 downloaded from iTunes? I'm wondering because I am considering dumping my iTunes collection off my iPhone to replace it with synced items from Rdio.
Yup - a Synced song should take up about the same amount of space that an mp3 stored elsewhere would.
another question for you, Madelyn (since you seem so helpful) - how does the space on my iPhone that is taken up by Rdio sync'd tracks show up when looking at my iPhone Summary in iTunes? Not as Audio, I'd think because that's strictly in the native iPod app, right? So does Rdio sync music show up as "Apps"?
Synced Rdio tracks will show up in combination with what the Rdio app itself is taking up on your phone (if you connect with iTunes on your computer, you can view this information directly).
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