When our kid was 2 and a few months we set him up with an old-school touchscreen. He had no problem playing games that would be hard for a 3.5 yr old with a mouse. May not sound like much, but a year at that age is huge, and even at 4, as the article states, kids are just barely getting the hang of a mouse. By 4, our kid was a mouse jockey. Transitioning from touchscreen to mouse was trivial.