It is an Google tutorial on how to optimize a mobile retail apps and sites. A good reference for developers to think with product mindset, and understand “why” we need to implement the feature like this, not only “how”.

Core principle

Put users at the center of design

• Provide clear utility before asking users to register
  • Allow user to use shopping chart before register
  • Only ask user to register when necessory
  • Also can let user checkout without account
• Use the same language as user
  • Use exactly the same word on copywriting
• It is difficult to type on mobile device (in search field and form)
  • Help User fix typo and provide auto-complete
  • Provide number pad for input numbers
  • Auto-populate, auto-capitalization, and credit card scanning are useful
  • Make password authentication a frictionless experience
    • Oauth / finger print is a good idea
• Ads should not block the content
  • Sounds like common sense, but still lots of sites & apps have full screen ads.
    • May be they only can earn money from ads.
• Provide full product details in a clear way
  • You should provide the details even the product is not available
  • Let user zone the image of product
  • Show how much do they save when there are discount
  • Show in-store availability
  • Display shipping info on item page
• Allow user give reviews and filter others review
  • Distribution of the user rating
  • Show the highest and the lowest rating
  • Encourage consumer-generated content
• Show related product when you think user want it
• Allow shoppers to continue shopping after adding an item to the cart
• Let shoppers edit the cart
• Resurface promotions, deals, and coupons at checkout.
  • Let user use them easier
• Show users the checkout process is secure
  • Like HTTPS and explain what is it to user
• Provide multiple third-party payment options
• Provide a detailed summary after purchase
• Ask for permissions / data when necessory
• Make customer service information easy to locate
  • Don’t put it in menu, put it on footer or some where easy to find
• Highlight the promotion in all product pages