Now that Apple is blurring the lines between its mobile tablets and PCs with the iPad Pro, it's tempting to imagine iOS and OS X merging into a single operating system (Windows 10-style) that works on virtually every device the company makes. You'll want to put any such ideas on hold, though. In a chat with Box's Aaron Levie, Apple chief Tim Cook dismissed the prospects of unifying iOS and OS X. It "subtracts from both," he said, arguing that you "don't get the best experience from either." This isn't a completely new idea from Apple (it once explained in detail why OS X doesn't have touch), but it's clear that Cook doesn't feel any pressure to follow in Microsoft's footsteps on this front.