I have a Samsung Galaxy Stardust with Android 4.3. In the email app, under security options, there is an option that says "encrypt all outgoing email". But my understanding of S/MIME is that in order to encrypt e-mail to someone, I have to have their public key. So it seems like this option can't really do what it says it does.
It likely means to use SMTPS, not S/MIME or S/GPG.– Lie RyanAug 16, 2015 at 2:14
@LieRyan, when you set up a mail account, there are settings for communicating with the mail server with SSL, so if "encrypt all outgoing email" meant the same thing, that would be redundant.– JWWalkerAug 16, 2015 at 14:35
It actually gets the public key of the receiver before sending the email. So yes, it could do what it says.
Gets the public key how? Unless that person has already sent me a signed message, I don't see how it would be able to get the public key.– JWWalkerAug 16, 2015 at 14:32