A team of scientists at Newcastle University in the UK managed to reveal a user's phone PIN code using its gyroscope data. "In one test, the team cracked a passcode with 70 percent accuracy," reports Digital Trends. "By the fifth attempt, the accuracy had gone up to 100 percent." From the report: It takes a lot of data, to be sure. The Guardian notes users had to type 50 known PINs five times before the researchers' algorithm learned how they held a phone when typing each particular number. But it highlights the danger of malicious apps that gain access to a device's sensors without requesting permission. The risk extends beyond PIN codes. In total, the team identified 25 different smartphone sensors which could expose compromising user information. Worse still, only a small number -- such as the camera and GPS -- ask the user's permission before granting access to that data. It's precise enough to track behavior. Using an "orientation" and "emotion trace" data, the researchers were able to determine what part of a web page a user was clicking on and what they were typing. The paper has been published in International Journal of Information Security.