For hosting common files it's ok. Also it is on Android too do, great to transfer files between your Windows and your phone. But if you want better security you have to subscribe a monthly offer.
Dropbox - Online Sync and File Sharing
3uTools - 3uTools is a most efficient iOS file and data management tool for Apple users.
Google Drive - Access and sync your files anywhere
Blackra1n - (This is an OUTDATED jailbreaking method.)
Mega - Secure File Storage and collaboration
greenpois0n - Greenpois0n performs an untethered jailbreak for iOS 4.