An Android mobile application designed to extract user contact lists without their knowledge has been in circulation masquerading as power-saving software, an analysis by security technology firm Symantec showed Wednesday.

Called Denchi Nagamochi (For Longer Battery Life), the application bills itself as enabling smartphones running on Google's Android operating system to run for twice as long. But in reality, the application does not have such a feature, according to the security company.

The application "takes advantage" of users' desire for longer battery time, a Symantec official said. "Users should beware of applications which do something different from what they say they do."

Smartphone users first receive an email message featuring the application. Once it is downloaded, a message pops up saying the application is not compatible with the smartphone in use. Below the surface, however, the application has extracted all the names, phone numbers and email addresses on a user's address book, according to Symantec.

The email message is allegedly being sent by a group running a dating site. Symantec says the personal data are believed to have been collected by the group in order to send email messages about the dating site to potential customers.