The Carpocrates were a Gnostic cult that developed in the first century. According to Clement of Alexandria (Strom. 3:431) the epistle of Jude was written specifically to counter their heresy. Tertullian (A.E. 3) says first Carpocrates sprung up, then the Apostle John's Arch enemy Cerinthus formed his cult, then after his death Ebion added Gnostic teaching to the Jewish Ebionites creating the Gnostic Ebionites. Victorinus (Commentary on the Apocalypse ch. 11) says the Apostle John wrote 1 John to counter the teachings of Cerinthus, and that the Gnostic schools of Valentinus, Cerinthus, and Ebion were rapidly spreading across the land. So all these heretics were in existence in the time of Jude and John.

The teachings of Carpocrates are as follows:

1. Slander Nicolas and Mathias by saying they taught fornication is no longer wrong.
2. We are imprisoned in a cycle of reincarnation by those evil creator angels. (compare to Scientology)
3. We can break the cycle only by experiencing all forms sin and righteousness.
4. Practice magical arts with incantations and spells
5. Invoke the aid of subordinate demons and dream-senders
6. Have voluptuous feasts which include gluttony, drunkenness, and fornication.
7. Jesus was the son of Mary and Joseph. There was no virgin birth.
8. Jesus was just a man with a pure heart because his soul was with a pure god before incarnation.
9. Some of them are more pure and advanced than Jesus

Notable points:

1. Their disciples had a tattoo on the back side of the right earlobe.
2. Used small Idols of Jesus, Aristotle, Pythagoras, and other people and angels, who they said were emanations of the pure god. (Compare to Bahai) They would adorn the idols with wreaths, garlands, and other ways to honor/worship them.

Information taken from:
Irenaeus Against Heresies, Tertuillian Against Heresies, and Hypolytus Against Heresies