Nice timing: On the same day that Apple upgraded Apple TV by adding more content to its Web TV box, Google upgrades Chromecast, its Apple TV competitor — by making it more appealing to Apple users. The upgrade comes via a new iOS app, which is something Google had previously promised. There’s nothing earth-shattering here, but the app will make it easier for people to use Chromecast with iPhones and iPads as their primary controllers. The big picture here is that Apple TV is, for better and worse, firmly part of the Apple ecosystem — it’s designed to be used in conjunction with Apple’s iTunes content, with other iOS devices, and Apple has tightly controlled the number of third-party apps on the box. But from the get-go, Google has said that its $35 dongle would work with all kinds of hardware, and today’s news just underscores that idea.