Peter: Formerly "Simon," renamed "Kepha" or "Cephas" by Our Lord; preached in Antioch, Pontus, Galatia, Cappadocia, and Asia Minor, Rome; headed Roman Church (was first Pope); crucified upside-down in Rome, Italy; relics at St. Peter's Basilica in Vatican City. Symbols: the Keys; upside-down Latin Cross; book. Feast: June 29 (along with St. Paul); August 1 (St. Peter's Chains).

Andrew:  Peter's brother; preached in Scythia; Epirus; Achaia; Hellas; Cappadocia, Galatia, and Bithynia, Scythian deserts, Byzantium;Thrace, Macedonia, Thessaly, and Achaia; crucified in Patrae in Achaia; relics at Cathedral of Amalfi, Italy. Symbols: X-shaped Cross; anchor; fish; fishing net. Feast: November 30.

James the Greater:    He and his brother (John) nicknamed by Jesus "Sons of Thunder" (Boanerges); a son of Zebedee; preached in Spain; beheaded by Herod Agrippa I to please the Jews; relics at Compostela, Spain. Symbols:
seashells; pilgrim's staff; scroll; book; floppy hat; trampling a Moor; mounted on horseback. Feast: July 25.

John:  He and his brother (James the Greater) nicknamed by Jesus "Sons of Thunder" (Boanerges); a son of Zebedee; the disciple whom Jesus loved; Evangelist; preached in Asia Minor (Ephesus). Symbols: chalice; eagle;
serpent; sword; cauldron. Feast December 27.  

Philip:  Preached in Hieropolis in Asia (?); relics at church of the Dodici Apostoli in Rome, Italy. Symbols: basket of loaves; T-shaped Cross. Feast: May 11 (with St. James the Less)

Bartholomew:  Preached in India, Mesopotamia, Persia, Egypt, Armenia, Lycaonia, Phrygia, shores of the Black Sea (?); beheaded or flayed alive and crucified, head downward in Albanopolis in Armenia; relics at 

St. Bartholomew-in-the-Island in Rome, Italy (?). Symbols: tanner's knife; flayed skin. Feast: August 24.

Matthew:  "Levi"; Evangelist; preached in Ethiopia to the south of the Caspian Sea (not Ethiopia in Africa), Persia and the kingdom of the Parthians, Macedonia, and Syria, and to the Hebrews generally (?). Symbols:
angel/man/winged man holding a pen or inkwell; bag of coins, money bag, money box, or purse; spear; sword; halberd; lance. Feast: September 21.

Thomas:  "Didymus," meaning "Twin"; familiarly (not Scripturally) known as "Doubting Thomas"; preached in India; pierced through with spears by four soldiers at Syriac Mazdai; relics in Santhome Cathedral, Chennai, India.
Symbols: T-square; spear. Feast December 21.

James the Less:  "James the Just" or "James the Younger"; son of Alphaeus (Clophas) and "brother of the Lord"; Bishop of Jerusalem Church; epistle writer; killed by Jews by being thrown off the Temple and clubbed to death.
Symbols: fuller's club; book; windmill. Feast: May 11 (with St. Philip)

Jude:   "Thaddaeus"; "brother of James (the Less)"; epistle writer. Symbols: shown with medallion with profile of Jesus around his neck; shown with flame above his head; oar; boat; axe; book; pen. Feast: October 28 (with St.
Simon).

Simon:  "Simon the Zealot" or "Simon the Canaanite." Symbols: fish(es); man being sawn in two longitudinally; saw; lance. Feast: October 28 (with St. Jude).

Judas Iscariot: Betrayed Jesus.  He was replaced by Peter (Acts 1:16-25) after his suicide by Matthias (St. Matthias's Feast: February 24).