Add items from shopping list to Wunderlist
Note: This assumes the gmail address is the same used for Wunderlist. You will also need to turn on "Mail to Wunderlist" integration in Wunderlist. This recipe emails to item to "email@example.com" and adds the item to the specified default list. Please checkout https://www.wunderlist.com/blog/mail-to-wunderlist/ for more information.