In the wake of Apple's admission that mobile iOS apps have had access to users' contact data without permission, Google announced that its development model makes it impossible for apps on an Android phone to share personal data with an app developer unless users agree to do so.
Tim Bray, Google's head of Android developer relations, tweeted that access to a user's contacts requires explicit permission. Users are presented with a list of permissions requested by the app developer before the app is installed. Google has said that a basic Android app has no permissions associated with it and therefore cannot "do anything that would adversely impact the user experience or any data on the device," according to Google.
Users can only install an Android app if they agree to all of the permissions requests.