Before installing an app it's good to know just how much of your personal information it has access to and what it may do with it. App Advisor from Secure.me lets you search a wide variety of Facebook apps to see just how safe they are.
Just visit the App Advisor Homepage, enter the apps name in the search box and then search for it's information page. There you will find information on the apps Permissions, App Behavior and User Ratings including detailed information on how the app has to access your personal data, the apps behavior after connecting and what users think about the app.
An example of when an app reportedly has too much control can be seen on the FarmVille app reputation page.
If you find an app that has too many permissions for your taste you can remove it in your Facebook App Settings page.
Other App Advisor tools from Secure.me:
App Advisor Extension for Chrome
App Advisor Firefox add-on
secure.me for iPhone, iPod Touch and iPad
Secure.me also has other Facebook privacy controls including:Privacy Control
Reputation Guard
Child Safety