Boxcryptor is an end-to-end encryption service to protect your cloud hosted data, it ensures that only you can view your data. It works with lot’s of cloud storage providers, for example Dropbox, Google Drive, OneDrive, etc. The service can be accessed through several devices (PCs or Smartphones) via installed applications or web portal.
The service has several plans for individual users and companies. With the free account offering you can have a single cloud provider, 2 devices and 2-factor authentication.