I’ve got an iPad and iPhone, I only got the small ones (16GB) and with a significant amount of music, I’ve frequently had to clear off less used apps for space. Then yesterday I thought about it some more, and remembered the tickbox in iTunes that says “Convert higher bit rate songs to 128 kbps AAC.”
I didn’t really think most of my library was of high enough bit rates to really benefit from conversion, but thought I would try it anyway.
Well, a few hours later, after iTunes finished converting everything, I had reduced space usage of music on my iPhone from 11.1GB down to 8.4GB. A pretty significant difference. So I’m pretty pleased.
To summarize, if you’re short on space on your iDevice, you might try this one out.