I'm one of Inky's core developers. Thanks for the support Product Hunt! We're really excited to bring end-to-end encryption for email to everyone, on any device, without complicated setup. Digital signatures are also built-in, so your friends can trust mail is from you and avoid phishing scams. This new version also features many new usability enhancements and rock solid push notification support for new mail.
We've posted a detailed white paper about the cryptography details if you're into that: http://inky.com/secure (link to PDF is down the page a little)
@mothore@erictwillis Yes, for the automatic and convenient key management, both parties do need to use Inky. However, it is all based on S/MIME, and we offer the ability to export your certs for use in other clients.
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