Hugh Pickens writes writes "Computerworld reports that a rogue Android app is hijacking smartphones and running up big texting bills to premium rate numbers before the owner knows it. Chinese hackers grabbed a copy of Steamy Windows, a free program, added a backdoor Trojan horse to the app's code, then placed the reworked app on unsanctioned third-party "app stores" where unsuspecting or careless Android smartphones find it, download it and install it. "This one stands out," says Vikram Thakur, a principle security response manager at Symantec. "It's pretty comprehensive in what it's doing." The app also has a built-in filter that blocks incoming texts from the user's carrier, a trick it uses to keep victims in the dark about the invisible texting. "It monitors inbound SMS texts, and blocks alerts telling you that you've already exceeded your quota," says Thakur adding that smartphone owners won't be aware of the charges they've racked up texting premium services until they receive their next statement. "If you're hell-bent on using [unauthorized app stores], look at the permissions the app requests when it installs. A [rogue] app will request more permissions than the legitimate version.""