From Secomba: BoxCryptor secures your data in the cloud, no matter if you use Dropbox, SkyDrive, Google Drive, or any other cloud storage provider. Access your encrypted files on all devices. BoxCryptor is available for Windows, Mac, Android, iPhone, and iPad. It is also compatible with EncFS-Linux. Secure your files the quick and easy way. BoxCryptor is free for non-commercial use.
read more +