Khoi Nguyen, Enterprise Mobility Group Product Manager at Symantec via eWeek:
Apple’s certification and rigid control over what applications can be posted on the App Store protected users, Nguyen said. The iTunes App Store acts as a certificate authority to sign the app and is the only source for non-jailbroken iOS devices. Google’s “less rigorous” system helped trigger the increase in Android malware because it was easier to get malicious apps onto the Android Market, Symantec found. Luckily for Google, most Android malware to date hasn’t had a significant impact on users yet.