Google has unveiled a service called Bouncer that scans apps and looks for known malware as well as potentially malicious behavior. The Android Market, which is the official app store for Android users, has been plagued by a number of incidents in which attackers have inserted trojaned versions of legitimate apps or malware-infected apps into the store. Google officials didn t specify exactly when the service was deployed, but said there was a 40 percent drop in downloads of potentially malicious apps from the market between the first six months of last year and the second half of the year.
Source: https://threatpost.com/google-begins-security-review-process-android-apps-020312/76169/