Yes, it's necessary it will act as a shield against key scratches. In fact, ditching the screen protector can save you money and make your phone more pleasant to use. The thing is phone screens are pretty easy to replace. And it helps reduces eye strain making reflections less distinct, diffusing the glare. However, newer screen protectors use chemical treatments to provide an additional screen protector layer. It protects against dirt and also has surface coatings a lipophobic layer that protects against the natural oils in your fingers accumulating on the screen and a hydrophobic coating that repels water. A small price in exchange for comfort, convenience, and a screen full of micro scratches is still a good deal.