Screens on smartphones vary largely in both display size and display resolution. The most common screen sizes range from 3 inches to over 5 inches (measured diagonally). Some 6-8 inch screen devices exist that run on mobile OSes and have the ability to make phone calls, such as Huawei Ascend Mate, Asus Fonepad and Samsung Galaxy Note 8.0. Ergonomics arguments have been made that increasing screen sizes start to negatively impact usability.