Red X is now a anti-hero and was Robin's "villian identity". He did receive a Communicator after the episode X.
Red X was hired by Slade to destroy the Teen Titans. He actually got arrested by the Police for failing to destroy the Titans.
Red X got freed later. He became a villian, but he actually left to his place so that Robin stole his costume to disguise as Red X.
Red X took his costume back to his place and quit working for Slade. He became a anti-hero.
Red X joined Teen Titans after he worked for Professor Chang.
Teen Titans Animated Series
Originally, Red X was an identity Robin had conceived for an unsuccessful attempt to get closer to Slade ("Masks"). In third season's "X" the Red X suit is now in the possession of an unknown culprit who keeps appearing as an antagonist, though not an outright adversary, of the Titans.
Red X's personality is the one major difference between him and Robin. While Robin was Red X, he was even more serious than normal and kept his goal of capturing Slade as his top priority. The new guy, however, is a thief who doesn't want to take over the city or threaten it, but is "just looking out for number one", i.e he steals for the money. When the new Red X first appeared and engaged in battle with the Titans, there were many signs to showcase that there was a new person under the mask. This Red X is revealed to be far less serious, finding his battle with the Titans amusing and being more concerned with messing with them, than getting what he'd come to steal.
On the other hand, Red X is more of an anti-hero than a villain. He helps Robin against Prof. Chang and helps free the rest of the Titans. In "Revved Up", he enters the race for Robin's personal secret, putting himself in a personal duel with his Titan counterpart. But after Robin saves his life, he takes out the other villains participating in the race, tells Raven and Starfire that "we're even...for now" and disappears. He has since become one of the most popular characters to have appeared on the series.
Red X's powers derive from his suit, which allow him to teleport. The belt relies on power from a source called "Xenotoium". His X-shaped palm gloves can form x-shaped projectiles which can act as shuriken, saw blades, restraints, timed explosives, instant openings and other functions.