Apple has finally ditched the iPad 2 and replaced its lowest- priced iPad with the iPad 4 with Retina display. It's a move that's probably come not a moment too soon, truth be told, as the iPad 2 has been around now for a long, long time. It's also likely to have happened because the price difference between the old iPad 2 and the newer iPad Air and iPad Mini models just was not being enough to justify sticking with the old stalwart.