gistfile1.m

#include <MailCore/MailCore.h>

...

-(void) sendEmail:(NSString *) message
{
    MCOSMTPSession *smtpSession = [[MCOSMTPSession alloc] init];
    smtpSession.hostname = @"smtp.gmail.com";   // SMTPサーバのアドレス
    smtpSession.port = 465;
    smtpSession.username = @"moemoe";           // SMTPサーバのユーザ名
    smtpSession.password = @"tsun dere";        // SMTPサーバのパスワード
    smtpSession.authType = MCOAuthTypeSASLPlain;
    smtpSession.connectionType = MCOConnectionTypeTLS;

    MCOMessageBuilder *builder = [[MCOMessageBuilder alloc] init];
    MCOAddress *from = [MCOAddress addressWithDisplayName:nil
                                                  mailbox:@"from@mail.com"];    // 送信元メールアドレス
    MCOAddress *to = [MCOAddress addressWithDisplayName:nil
                                                mailbox:@"to@mail.com"];        // 送信先メールアドレス
    [[builder header] setFrom:from];
    [[builder header] setTo:@[to]];
    [[builder header] setSubject:@"ここにサブジェクト"];
    [builder setHTMLBody:message];
    NSData * rfc822Data = [builder data];

    MCOSMTPSendOperation *sendOperation =
    [smtpSession sendOperationWithData:rfc822Data];
    [sendOperation start:^(NSError *error) {
        if(error) {
            NSLog(@"Error sending email: %@", error);
        } else {
            NSLog(@"Successfully sent email!");
        }
    }];
}