The document discusses the key principles of continuous experiences across devices: 1) seamless synchronization of data across devices via push notifications or thick client apps, 2) appropriate features tailored for each device's usage, 3) consistent design for familiarity, 4) optimized interaction fitting each device, 5) respect for personalization while allowing customization, and 6) integration with operating systems and apps to extend services. It provides examples of both good and bad implementations and emphasizes that the experience should be greater and more valuable than individual devices.