Your reasoning is "the tablet market is so large"?
The tablet market should probably be called the iPad market, since the iPad is so dominant. Since iPad is wiping the floor with all other "competitors", I'd say they are doing just fine without producing lots of unnecessary sizes.
The tablet market should probably be called the iPad market, since the iPad is so dominant. Since iPad is wiping the floor with all other "competitors", I'd say they are doing just fine without producing lots of unnecessary sizes.