A terrific article that really gets at the heart of how UX’ers can use the Lean process. A Guide To Validating Product Ideas With Quick And Simple Experiments | Smashing Magazine.
The First Time UX blog reviews the sign up flows of many apps. It’s super helpful to have all of these screenshots and notes in one place. And here are some tips for designing your app’s first time UX: First time user experiences in mobile apps
I really enjoyed this series of posts on running design sprints. How To Conduct Your Own Google Ventures Design Sprint