BooleBox VS ZixEncrypt

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

NeoCertified Secure Email - NeoCertified is a solution that provides secure email encryption for businesses and organizations across all industries, including healthcare, finance, legal, non-profit and education.

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.

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

Encyro - Use Encyro to send sensitive messages and files to your customers and service providers, including accountants, loan officers, health coaches, and others. Stay organized and forward documents from your mobile device.