Using Outlook for iOS in business environments for email and scheduling
I have this same problem. Sectigo or Actalis s/mime certs. All work on Office15, Office16, O365, Outlook for Mac, and other mobile apps like 9folders. Also does the iphone IoS version support ldap address books like desktop Outlook does? Our intl setup relies on userSMIMECertificate AD attribute since it scales better than GAL. Thank you.