Some time ago we have developed basic shared shopping list web application. It was something like hobby project back then, but now we have decided to make it better by adding more advanced features.
Grocify is a web application that allows you to share shopping list with your close family, roommates or whoever. After someone from your group adds an item to shopping list, any other member can use a phone to see this list while in the store. No need to call or text your household members for this purpose anymore.
To see details and create a free account, just go to Grocify website.