What do you mean "expand your BB's memory online"? The only way to expand memory is to delete unused apps or shrinking down the OS or you could go buy a memory card to store your multimedia files like music, pictures, and videos.
Yeah, Dropbox is a good app. I backup all my pics and videos on there so I can save memory on my memory card. Or if you don't have a memory card and use your internal memory for your pics then this is a good option.
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A 8g micro sd card at most is 20 dollars. I have 1150 songs and still have 1g for pics and videos. That's not bad bro! You can get a lot of memory back just by deleting all the crap you never use. Voice dialing, ect. I know u said free but 20 isn't bad.
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