(Copied from my original post on my tech blog.) A few days ago, a message popped up on my iPhone, saying that Im almost out of storage on my 5GB iCloud account. It turns out that my iPhone 5 iCloud backup was ridiculously large, especially considering I tend to keep my camera roll empty. Why would the backup be so huge? After a quick investigation, I found out why. One thing to note is that this problem, at least on my end, occurred in iOS 5 as well as iOS 6. More on that in a bit Because I rarely keep anything inside of my Camera Roll, I knew that it couldnt have been related to anything regarding my photos. When I bought my iPhone 5, I started fresh. Because of how locked-down iOS is, a user cant simply browse all of the devices filesystem (without a jailbreak at least, however there are ways to view directories, but not all of them). Fortunately, DiskAid is able to view the Media folder, located in /var/mobile/Media. I went through these folders to find something suspicious, but couldnt find anything. Long story short, whenever you clear out a conversation in the Messages app, whether it be an SMS or an iMessage, the app might not actually be removing all of your sent and received attachments. This also occurred in iOS 5, which is why I always used iFile to periodically remove everything in /var/mobile/Library/SMS/Attachments, as the Messages application wouldnt do that, for whatever reason. I found this out by first doing a completely new device backup inside of iTunes, and using a free Mac OS X application called iPhone Backup Extractor to take a look at what was actually backed up. Sure enough, the Attachments folder within my particular backup is well over 4GBs in size, despite me deleting all of my open conversations prior to creating the backup. I found attachments that I sent and received over a month ago, which could also be thought of as a potential security threat. So, how would one be able to solve this? Unless youre jailbroken, theres nothing you can do, but hope that Apple fixes this in iOS 6.0.1. If you happen to be jailbroken, whether it be on iOS 5 or iOS 6, you can easily use iFile to navigate to the /var/mobile/Library/SMS/Attachments folder to delete everything in there.