I’m not sure how new this is however Android users who say “Ok Google” and then “Add xxx to my Shopping List” will find that Google Keep is able to maintain a shopping list for them.
There doesn’t seem to be anything special users need to do other than say “Add xxx to my yyy list”. While the trick might seem specific to shopping lists it actually will create just about any type of list. For example “Add Pencils to my Office List” creates a list called Office and adds Pencils onto it. If Google Keep finds an existing list which is close in name to the one you are asking to add an item to, then your item is appended onto the list.
Google Keep also will remind you based on location, so don’t be shy about setting a reminder so that the list appears the next time you pull into your local shopping center!