You no longer need to dial 1933. Your messages are recorded on your smartphone as audio-files. Did one of your known contacts leave a message? Their name and number are automatically recognised. You can also:
In practical terms, you choose the message you want to hear by selecting it from the list.
Other highly convenient features:
Activate/deactivate Visual Voice Mail
Available from model 4S with version iOS 8.x and higher.
Activate/deactivate Visual Voice Mail
Available from Android 2.3.