Microsoft is currently testing support for S/MIME encryption in Outlook for iOS.
S/MIME allows users to encrypt emails and digitally sign them. The feature is a widely accepted protocol for sending digitally signed and encrypted messages.
Signed, sealed and encrypted. ? The first phase of S/MIME support is now available in @Outlook for iOS TestFlight. ?
Please try manual cert installation and send us feedback / report issues. Automated delivery is coming later to iOS. Android support for both is very soon. pic.twitter.com/VwAa5lHB7F
— Michael Palermiti (@MPalermiti) June 24, 2019
The feature is currently in Testflight and will be coming to Android soon.
If you want to join Testflight for Outlook, you can sign up here.
Outlook for iOS can be found in the App Store here.