Complex sentence: Commercially produced and sold e-books are usually intended to be read on dedicated e-readers, however, almost any sophisticated electronic device that features a controllable viewing screen, including computers, tablets and smartphones can also be used to read e-books.
Split into simpler sentences: Commercially produced and sold e-books are usually intended to be read on dedicated e-readers. However, almost any sophisticated electronic device that features a controllable viewing screen, including computers, tablets and smartphones can also be used to read e-books.