OK, so I've been happily using my iPhone the past two months, and filled my iPhone over time till it had about 4 and a half gigabytes left. So, today I needed to install an app, and I get the message "not enough storage". I go ahead and see what iTunes says, and indeed, I am almost out of space. I noticed maybe 4.2gigs were taken up by "other" which, last time I checked, was only a few hundred megabytes. Now, I don't use the iPod function, but I do use Cydia apps a lot. So, what caused this to happen? and how do I fix it?