I know, some of you are really annoyed by this shit, right? And go crazy with Mr. Google to find a latest solution? But end with found some old and expired trick. :>
Why don't you guys just unfriend or block the person who send the invitation? Oh maybe you guys still wanna be friend with the 'sending machine'? i guess/ :-P.
So instead of blocking these annoying people FOREVER or tell them directly, here the latest solution for the new Facebook settings without block the account, but only block an invitation from them.
1. Go to 'Privacy Settings'
2. Manage 'Blocked People And Apps'
3. Go to 'Block app invites' and then at the 'block invites form' section. Then the next steps, you know what to do. Hey look, someone has been blocked by me XD.
Lastly, enjoy your Facebook notifications without any app requests! :))