Out of Milk has two versions available to choose from:
The free version of Out of Milk is the best list making application you can find on the Android Market (and soon, the iPhone!). Out of Milk includes tons of great features: Syncing and Sharing lists in real-time, backing up your data, access to our amazing website, and more! It has all of the features you need to easily and efficiently manage all of your lists - shopping, pantry, and to do. Get it on the Android Market now!
The Pro version of Out of Milk is an optional upgrade for users who want a little bit control over their app. Use a widget on a phone homescreen, change the Out of Milk default theme, and define advanced actions such as single and double tap behaviors with the Pro upgrade.