They supposedly use Keynote, but I think with these presentations it's more likely custom motion graphics in After Effects or possibly Final Cut Pro if Apple is imposing in-house software.
Apple have an in house team that specialize in just these kind of keynote slides. I imagine it's worked up mostly in keynote, maybe with a bit of extra software like After Effects on the side.
They employ an outside company to do the bigger CG graphics, promo introductions and renders of the devices
They employ an outside company to do the bigger CG graphics, promo introductions and renders of the devices