Berkley scientists launch Carat, an app to monitor phone battery usage

A group of scientists at the University of California at Berkley have developed a mobile application that monitors your phone's battery usage. The application will tell you which of your phone's other apps are draining your phone of its battery and which apps contain the most number of battery draining bugs. They wrote on their website, "An energy bug is a system behavior that causes unexpectedly heavy use of energy and which is not intrinsic to providing the desired functionality. We aim to identify and help diagnose energy bugs in mobile devices by performing distributed, low-overhead sampling, aggregating these data, and applying statistical methods to identify the apps, behaviors, and configurations that are associated with high energy consumption."

Screenshots of Carat for iOS

The application essentially can tell you that using your favourite e-mail application is draining a large amount of your battery when you're using it over GPRS/3G, as opposed to over Wi-Fi. Furthermore, the developer behind the e-mail application can be informed of a bug that might cause the issue and, of course, issue a fix for it. The website essentially says that the service informs users of what's draining their battery in exchange for usage data. They write in the application description that the data is collected from your phone and delivered to their servers where they apply a number of algorithms to give you your results. However, they specify that none of the data they collect will be able to identify you personally.

The Carat description specifies that apps can either be considered 'hogs', where they intrinsically drain a large amount of battery, or 'bugs' where they contain bugs that will drain battery. The description says that neither of these two things are necessarily bad, however a smartphone user could use this information to adjust their behaviour.

Features of the app include:

• Action List telling you how to improve your battery life and by how much
• Device information detailing exactly what data we are recording
• Reports apps that are using lots of energy and whether that is happening on other devices, too
• Detail views let you dive down into the data and see graphs of energy use
• Low-overhead sampling requires almost no energy or CPU
• J-Score tells you how your battery efficiency compares to other users
• Sharing features let you post/tweet/blog about your experience; more users means more data which means better recommendations for you

The app is available for free from the iOS App Store as well as Google Play store.