Is it permissible to read the Quran from the Mushaf or a phone without ablution?

There is no harm in merely reciting the Qur’an for someone who is not in a state of major ritual impurity. However, it is not permissible for someone who does not have ablution to touch the Mus'haf (the physical copy of the Qur'an). As for mobile phones and similar devices, there is no harm in touching them and reading from them, even without ritual purity, and even for someone in a state of major ritual impurity (junub), because it is not considered a Mus'haf. The letters that appear on it are vibrations that form the letters when requested and disappear when moved.