I got really frustrated today when I added an application to my Facebook account by accident, well half accident. Adding the app was not the frustrating part. Deleting the application from my account is what got to me. There is no apparent way to do it. After a search on Google I found out how to do it. If your here to find out how to delete apps from Facebook see bellow.
What I found very interesting was the number of apps I had in my account. There were tons of them and some of them were very old. Most of these apps I no longer use so why should they still have access to my account. I started deleting them. Facebook does not provide a fast way to delete unused apps though. It takes three clicks to get rid of them and you have to do it for each app. What a PAIN! One more reason to use Facebook less. I know I can simply not allow sites to add the apps in the first place but that part is easy for them and for me.
How to delete a Facebook Application
Logg in to Facebook, click on the Account button at the top right of the page and then select the option that says “Privacy Settings.”
Once you have done this, near the bottom left of the page, click on the link that says “Edit your settings.”
Now, in the “Apps you use” area, click on the application you’d like to remove. If you don’t see the application listed, you can find it by clicking the Edit Settings button at the right extreme of this area.
Once you have clicked on the application’s icon, You will see a screen with the settings for that application. On that page, click the “Remove app” link. The system will ask you to confirm the action, and then the application will be removed from your account, which means that it will no longer have access to your data.
Source http://romcartridge.blogspot.com/2010/01/how-to-remove-facebook-applications.html