The last bit is particularly important. For the most part, the majority of smartwatches out there require it to be tethered to a smartphone. We suppose this makes sense because notifications received on the smartphone will then be relayed to the watch, and input on the watch will then be relayed back to the smartphone.
However with Android Wear 2.0, Google is trying to make it so that apps have the ability to communicate directly over WiFi, Bluetooth, or cellular without the need for an exclusive tethered connection to a smartphone. This will of course depend on the hardware features of your smartwatch, but presumably newer devices should not have a problem.
In addition to trying to cut the cord with smartphones, Android Wear 2.0 will introduce a new user interface which will see Material Design brought over onto it. It will sport expanded notifications, a darker UI, a “proper” keyboard, and support for new input methods like writing directly on the screen, along with Smart Reply, a feature that Google seems to be touting quite a bit these days.
There is also a new Fit Platform Activity Recognition API, which while it might seem like it’s catered more towards developers, ultimately this should result in the watch recognizing what you’re doing and launching the correct/appropriate fitness app for you.
Android Wear 2.0 will be released later today as a developer preview, but unfortunately compatible devices are limited to the Huawei Watch and the LG Watch Urbane Second Edition LTE. The update is expected to be released in the fall.