The Missal book is the norm used for Mass. iPads CAN be used IF AND ONLY IF a Missal book is not around.

Bishop advices use of IPad, tablet in lieu of Missal only during ‘emergency’.

Have you ever seen a priest use an iPad or tablet computers in saying the Mass and wonder if it is acceptable?

Even if the Catholic Church is gradually espousing the use of the internet and social media in its evangelization work, Church leaders are still hesitant in embracing technologies and innovation in the conduct of sacraments and rituals, like using the iPad or tablet computers in lieu of the Missal during the celebration of the Mass.