BoxCryptor - Boxcryptor encrypts your sensitive files before uploading them to cloud storage services like Dropbox, Google Drive, Microsoft OneDrive, Box, and many others.
iMazing - iMazing lets you transfer music, files, messages, apps and more from any iPhone, iPad, or iPod to a computer, Mac or PC. Manage and backup your iOS device simply without iTunes. (was DiskAid)
Mega - Secure File Storage and collaboration
Blackra1n - (This is an OUTDATED jailbreaking method.)
Google Drive - Access and sync your files anywhere
greenpois0n - Greenpois0n performs an untethered jailbreak for iOS 4.