You might want to start humming Garbage's "I Think I'm Paranoid."
A recent study by Lookout, who offer security data backup services for smartphones, offers up a worrisome look at how phone apps are accessing your personal information. The App Genome Project looked at 300,000 programs in both the iPhone's App Store and the Android Market. Aside from some general statistics (e.g. there's a higher percentage of free apps for Android phones, app downloads are expected to hit 50 BEELLION by 2012), the study also concluded that Android apps are somewhat less likely to access your current location or contact list — but also have a higher chance of containing 3rd party code that (again, in theory) be doing something unauthorized while you're not looking.