"Hey Siri" support and possibly wireless charging case alongside AirPower charging mat.
Android Wear Now Compatible With iPhone, iOS App Launches Today
Android Wear for iPhone has several features familiar to Android users, including third-party watch faces, fitness tracking, notifications, Google Now and voice searches. Android Wear for iPhone will also have Google apps such as Weather and Translate preinstalled, but third-party iOS apps are not supported due to Apple's restrictions.
Google has attempted to work around Apple's limitations, but Android Wear for iPhone still has some locked-down functionality compared to what is possible with a paired Android smartphone. Rich notifications, for example, are only supported for a handful of stock Google apps, while the selection of watch faces is limited due to the lack of third-party app support.
Android Wear for iOS is compatible with the new LG Watch Urbane, upcoming Huawei Watch and Asus ZenWatch 2 and all future Android Wear smartwatches out of the box. Android Wear for iOS does not officially support existing Android Wear smartwatches such as the Moto 360 or Samsung Gear, but most users find that older models do work after a factory reset.
The Verge has published an extensive hands-on of Android Wear for iPhone alongside the announcement.