Each week Ross Rubin contributes Switched On, a column about consumer technology. In the world according to Apple, there are OS X-based Macs and iOS-based iPads and, as it stands now in the era of disparate kitchen appliances, never the twain shall meet, even if they tend to borrow features from each other. Point the finger of blame at synthetic pointing devices that offer precision at the expense of intimacy. Google has played it a little looser with its two-pronged operating system strategy. It has reserved