4. what is friction?
physics:
friction is the force resisting
the relative motion
between two layers sliding
against each other.
Joshua Porter, bokardo.com
22. don’t punish the user for switching contexts
switch between reading and listening
to a book on Kindle and Audible
without losing your spot in the book
23. remove the need to make decisions
if you must have decisions,
then keep them few and simple
24. one click : remove the decisions for billing/shipping info