Cryptomator is a multi-platform transparent client-side encryption of your files in the cloud that protects your documents from an unauthorized access.

Features:

• Open source software: No backdoors - control is better than trust
• Client-side: No accounts, no registration, no data shared with any online service
• Works with Dropbox, Google Drive, OneDrive, Nextcloud and any other cloud storage service which synchronizes with a local directory
• Totally transparent: Just work on the virtual drive as if it were a USB flash drive
• AES encryption with 256-bit key length
• File names get encrypted
• Folder structure gets obfuscated
• Use as many vaults in your Dropbox as you want, each having individual passwords