How to change privacy level of a Facebook post? I'm using the official Facebook app and I've used it to update my status. Inadvertently, I made this status update public. Is there any way within the app, or the Facebook mobile website to change the permissions of a post to friends-only or a specific friends list?

The only way I can find of doing it is to either use the full FB website, or use Friendcaster instead. (Since some of my friends have set their accounts to not allow access from third party apps, I've switched back to the official app from Friendcaster).
I'm afraid that the native Facebook app is very limited in functionality. While it has improved (quite a bit) from its initial launch, there are still a lot of things you can't do in the app.

You may be able to do what you need from the mobile-optimized website (http://m.facebook.com) but most likely you're going to need to hop over to your desktop and use the full website in your desktop browser.