This Saint was from Bethsaida of Galilee; he was the son of Jonas and the brother of Peter, the chief of the Apostles. He had first been a disciple of John the Baptist; afterwards, on hearing the Baptist's witness concerning Jesus, when he pointed Him out with his finger and said, "Behold the Lamb of God, Which taketh away the sin of the world" (John 1.29,36), he straightway followed Christ, and became His first disciple; wherefore he is called the First-called of the Apostles. After the Ascension of the Saviour, he preached in various lands; and having suffered many things for His Name's sake, he died in Patras of Achaia, where he was crucified on a cross in the shape of an "X," the first letter of "Christ" in Greek; this cross is also the symbol of Saint Andrew.
Apolytikion in the Fourth Tone
As first of the Apostle to receive the call,
and very brother of the prince of them,
intercede O Andrew, with the Master of all of us,
peace to all the world to grant,
and to our souls His great mercy.
Kontakion in the Second Tone
Let us praise the namesake of bravery, the divinely eloquent and first to be called of the Disciples of Christ, the kinsman of Peter. As he called out to him in days of old, so now he calls to us, "Come, we have found Him for whom we yearned."
Source: Greek Orthodox Archdiocese of America, http://www.goarch.org/chapel/saints_view?contentid=316