I don't use any apps there.
[With this spare key, a third party can access your profile, photographs, chat logs, comb through your account for personal information, and even pose as you and post messages and communicate with your friends.]
http://www.securitynewsdaily.com/fac...fo-again-0780/
["Fortunately, these third-parties may not have realized their ability to access this information," Doshi wrote. "[But] we estimate that as of April 2011, close to 100,000 applications were enabling this leakage. We estimate that over the years, hundreds of thousands of applications may have inadvertently leaked millions of access tokens to third parties."]
http://www.pcmag.com/article2/0,2817,2385190,00.asp