Conectando-se a HTTPS com certificados autoassinados no iOS

Adicione o seguinte ao seu NSURLConnectionDelegate

- (BOOL)connection:(NSURLConnection *)connection canAuthenticateAgainstProtectionSpace:(NSURLProtectionSpace *)protectionSpace {
        return self.allowSelfSigned && [protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust];
}

- (void)connection:(NSURLConnection *)connection didReceiveAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge {
    NSURLCredential *credential = [NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust];
    [challenge.sender useCredential:credential forAuthenticationChallenge:challenge];
}

Para iOS 9, para desativar ATS, adicione o seguinte ao info.plist de seus aplicativos

<key>NSAppTransportSecurity</key>
<dict>
    <key>NSAllowsArbitraryLoads</key><true/>
</dict>