VeraCrypt - VeraCrypt is a free open source disk encryption software for Windows, Mac OSX and Linux.
BoxCryptor - Boxcryptor encrypts your sensitive files before uploading them to cloud storage services like Dropbox, Google Drive, Microsoft OneDrive, Box, and many others.
Knox - Knox offers easy disk image encryption and comes with a built-in backup service.
Google Drive - Access and sync your files anywhere
Cryptomator - When it comes to saving your files on a cloud server, it is important to ensure the security of those files. Keeping your delicate files out of the wrong hands can save you a lot of time and hassle. Read more about Cryptomator.
Mega - Secure File Storage and collaboration