Connected Nation: A Platform-by-Platform Best Practices Playbook
Both Google and Samsung have software initiatives that are similar to Apple's Continuity product. Samsung released a product called Flow, but unfortunately it only currently supports a few Samsung devices. Google's built Smart Lock into both Android Wear and Android smartphones. For example, Chromebooks can be unlocked when your phone is nearby.
In summary, there's no one-size-fits-all approach to servicing users across multiple devices. A unified desktop-mobile-internet of things (IoT) operating system has a few obvious benefits, but the risk will always be user experience — e.g., apps that can scale appropriately for the platform or take advantage of what the new hardware has to offer. The World Wide Web Consortium (W3C) has a set of standards for web and mobile web apps, but there isn't yet a common standard for "connected applications." Each of the platform owners have their approach to standardizing connected devices: Microsoft through Azure and a "small" version of Windows 10, Google via Brillio and Weave, and Apple via HomeKit and HealthKit.
Since it will be difficult for the platform owners to agree on a common runtime for apps, the lowest-hanging fruit is in a common communication protocol for connected devices. This is where the platform owners should come together, Weave and HomeKit/HealthKit, as well as Azure. Given Amazon.com's leadership in the cloud computing space, they should certainly be driving the other platform owners towards a set of standards.
The platform owners do seem to agree on one thing: your phone as your identity. This identity carries permissions to unlock other devices, to pay for items and services, and to provide a profile of work and activities.
This is the foundation of the multiscreen world, and the building block of technologies that will help consumers continue to be better connected and more mobile in the future.