BooleBox VS NeoCertified Secure Email

Box - Box offers secure content management and collaboration for individuals, teams and businesses, enabling secure file sharing and access to your files online.

Virtru - Virtru is your data privacy force field, wrapping and protecting emails and files wherever they're shared. Easy-to-use data security software for business. People also askIs Virtru Hipaa compliant?

Nubo - A self-hosted file sharing application in Haskell.

Paubox - Paubox provides HIPAA compliant email encryption without the hassle of extra steps.

Soonr - Soonr is a cloud-based document storing and file sharing system for the small and medium-size businesses.

Proofpoint Email Encryption - As email is the preferred medium for business communications, preventing confidential information from being leaked in outbound email messages must be a top priority in order to lower the risk of a data breach.