LAS VEGAS – Your smart phone applications are watching you — much more closely than you might like.

Lookout Inc., a mobile-phone security firm, scanned nearly 300,000 free applications for Apple Inc.'s iPhone and phones built around Google Inc.'s Android software. It found that many of them secretly pull sensitive data off users' phones and ship them off to third parties without notification.

That's a major concern that has been bubbling up in privacy and security circles.

The data can include full details about users' contacts, their pictures, text messages and Internet and search histories. The third parties can include advertisers and companies that analyze data on users.

The information is used by companies to target ads and learn more about their users. The danger, though, is that the data become vulnerable to hacking and use in identity theft if the third party isn't careful about securing the information.

Lookout reported its findings this week in conjunction with the Black Hat computer security conference in Las Vegas.

Lookout found that nearly a quarter of the iPhone apps and almost half the Android apps contained software code that contained those capabilities.