For hosting common files it's ok. Also it is on Android too do, great to transfer files between your Windows and your phone. But if you want better security you have to subscribe a monthly offer.
BoxCryptor - Boxcryptor encrypts your sensitive files before uploading them to cloud storage services like Dropbox, Google Drive, Microsoft OneDrive, Box, and many others.
Dropbox - Online Sync and File Sharing
Cloudfogger - Easy and secure encryption for the cloud. Provides security for all cloud storage services like Dropbox, OneDrive and Google Drive.
Google Drive - Access and sync your files anywhere
Mega - Secure File Storage and collaboration
Box - Box offers secure content management and collaboration for individuals, teams and businesses, enabling secure file sharing and access to your files online.