1. Personas

   Design for Weight Watchers members illustrated by product personas

2. Experience

   Design for the entire product experience rather than isolated needs

3. Context

   Keep context in mind – where’s the member coming from and where are they going

4. The 80%

   Optimize the design for the 80% use case - most members most of the time

5. Simplicity

   Design for simplicity while supporting functionality, visual language and brand

6. Patterns

   Design within the current product patterns when possible

7. Extensibility

   Create new patterns when existing patterns don’t solve a new problem. New patterns should be consistent and extensible.

8. Platform

   Patterns should follow the native platform while still serving the brand

9. Hierarchy

   Clearly define hierarchy and level of detail on each screen - focus on the main objective

10. Empathy

    Design with member empathy