Windows is the top desktop platform and a target-rich environment for criminals. It doesn't necessarily mean the operating system is any less secure than the competition. It's just getting attacked in far greater quantities. Android is king of the hill when it comes to mobility and it may be suffering a bit of the same fate.
With Android, though, it isn't just about market share. It is also how apps are loaded on the platform. With a model like Apple has with iOS and Microsoft has with Windows Phone 7, it is very difficult to get apps on the device without the app going through an audit to ensure it: does what it claims; doesn't violate a set of rules designed to protect the device, network, and user data; and most of all, doesn't contain malware. No process is perfect and surely somewhere in the 300,000-plus apps in the App Store there is some code that was written to cause some sort of mischief, but should that happen, Apple will just flip the kill switch and remove the app from your phone.
Android doesn't have those protections. First of all, the Android Market doesn't subject apps to the scrutiny that Apple does, and that has caused more than one app in the Market to be a source of infection. Just two months ago Google removed 26 malicious apps.
Secondly, even if Google tightened its application approval process, you aren't forced to use the Android Market exclusively. If you want an app on your iPhone, you are locked into the App Store. (This ignores those that jailbreak their devices. I ignore that group of people when it comes to security because they are deliberately bypassing built-in security features, so they're on your own there.) With Android, you can choose from a variety of markets, none of which are approved by Google, so who knows what you risk when downloading from those?
According to Lookout Mobile Security, half a million Android users were affected by malware in the first six months of this year.
If you are an IT manager, this should give you pause. It is one more thing to worry about when deploying devices. Educate your users on downloading from trusted sources and consider the various antivirus products for Android. Having a phone that is infected is a hassle and can cause data loss; having it cause the loss or theft of corporate data can be catastrophic.
Google should step up here and at least provide a marketplace that is as tightly run as the App Store is. That would give users a lot of comfort that, when downloading from the main source of Android apps, there should be very little to worry about.