Frontier has announced that the stand-alone version of Elite Dangerous: Arena has been pulled from the Frontier Store, Steam and the XBox Store. The decision was made after looking at metrics and discovering that most players play directly from the Elite: Dangerous in-game client. Though originally released as a stand-alone, the number of additional players in Arena did not increase.
Elite Dangerous: Arena continues to be available and supported as part of the wider Elite Dangerous game. Existing and new players that join the Elite Dangerous galaxy will continue to be able to enjoy the fast-paced action of Arena through the main menu. Existing Elite Dangerous: Arena client owners will still be able to enjoy Arena as they have always done.
Read the full announcement on the Elite Dangerous official site.