The series has had a significant impact on the development of console role-playing games, and introduced a number of features to the genre. Installments of the series have appeared on various computers, consoles, handheld devices, and mobile phones. Early in the series, the "Dragon Quest" games were released under the title "Dragon Warrior" in North America to avoid trademark conflict with the unrelated tabletop role-playing game "DragonQuest". Square Enix did not register the "Dragon Quest" trademark for use in the United States until 2002.