We’ve had quite a few BlackBerryCool readers who are concerned about how their personal data is being used, and want to know how to stop an app from having access to information such as their email address. There are apps on the market that are made so that the companies can grab email addresses which they then use to market their apps. These apps are often free to promote downloads, and they can access your Address Book as long as you accept the permissions. What you may not have known, is that you can edit the Default Permissions, so that your user data is permanently locked. To do this, go to:
Options > Device > Application Management > Menu > Edit Default Permissions > User Data > Deny.
This will prompt you of any software that is trying to access your user info and ask you if you want to allow or not.
Tip courtesy of @WrlessMerchant