not by everything but they are by the os and some games. Apps and games are made by very small dev teams sometimes literally just one guy. Its unreasonble to expect everything app/ game to be 100% utilised for everything. New stuff will be an time alot more stuff

Obviously were not talking about everything using a quad core +. Im talking about there not even 1 thing that utilizes a dual core.

To recap, if nothing uses it, than everything wont either. But ya hopefully in the nest few years we can start seeing some dual core aps, and a few yars after that quad core.