Codenamed "Raring Ringtail", this version was released on Apr 25, 2013 and is no longer supported since Jan 27, 2014. Questions about unsupported versions are likely to be closed as off-topic.
Code-named Raring Ringtail, this was released on 25 April, 2013 and was supported until January 27th 2014.
Ubuntu Flavors available under 13.04 (questions on all are allowed):
The 13.04 Ubuntu variants - Mythbuntu, Ubuntu Studio, Kubuntu, Xubuntu, Lubuntu, UbuntuKylin, Ubuntu Gnome - are not commercially supported by Canonical.
Ubuntu Editions available under 13.04 (questions on all are allowed):
Questions on are considered off-topic since it had reached the end of life.