According to a report from Kaspersky Labs, Android Malware has seen drastic increase Q2 2012. There are almost 3X increase in Malware App in Google Play Store in Q2.
According to report about 14,923 are reported as Malware this mark was too low in Q1 to around 5,441. These number sees this enormous change due to increasing popularity of SmartPhones and share of Android in the Market. About 49% of these apps are Trojan which steals contact data and other stricted data. About 25% are SMS Trojans which sends premium SMS without your will. Only 18% apps are those which takes control of your phone and 2%percent are extremely dangerous known as TrojanSpy.
So guys always download Apps by acting as human means reading permissions.