Shaykh Saalih al-Fawzaan said regarding touching the mushaf that it is not necessary to be in taharah and taharah is only for touching the mushaf directly due to the Hadith of Amr ibn Hazam: None should touch the Quran except those in taharah. The cellphone copies the Quran on it. That which is written on the screen of the Quran is not the mushaf. This is the cellphone and how can one read it, carry it, and touch it without a problem and without taharah? (As such) itt does not carry the ruling of the mushaf.
As such, the same applies to the ipad becase it is a screen. The lanjah has mentioned that the women can read the Qur’aan during menses.
~ Faisal Ibn Abdul Qaadir Ibn Hassan