Although i agree that gas cooktops have several advantages in cooking non westernized meals, rotis can definitely be made on induction. Been making them since many years now.
Heat a pan, until a small amount of ghee/butter melts when placed on it. Place the roti on the pan, and cook each side. You will know that it is done when the roti slightly puffs up.
True skill is in making rotis which stay soft in a hotbox.