What are some tips for deciding whether to get a 16, 32 or 64 GB iPhone 5? I have a 64 GB iPad, but I wouldn't need all of its videos and apps on an iPhone. My only other frame of reference is the amount of RAM and memory card usage on my Android phone. My needs and habits would be the same with the iPhone, so if I'm currently using XX GB across the RAM and SD card, is it reasonable to assume that that amount will be enough with the iPhone 5? One more question: How much of the iPhone's RAM is available to users? For example, on the 16 GB model, how much is consumed by the OS? Thanks.