App 'kill switch' defended as security precaution

Finnish developer Janne Kytomaki said he knew something was amiss last year when he noticed dozens of best-selling applications on Google's Android Market listing the same incorrect author.

Kytomaki ran tests, identified the mislabeled software as a fast-moving attack and published the findings online.

Google responded swiftly. It yanked the apps from the marketplace and, using a little-known tactic to keep the malware from spreading, flipped a kill switch that reached into more than 250,000 infected Android smartphones and removed all vestiges of the software. "I was positively surprised by how fast Google got the apps removed from the market and how fast they were able to roll out a tool for removing the malware," Kytomaki said.