Duplicate Cleaner For iPhoto (free for a limited time) is an easy to use app for zapping double images, even if they’ve been edited.

I see that there are quite a few apps: Photos Duplicate Cleaner, Duplicate Photo Cleaner, Duplicate Photos Fixer Pro, Cisdem Duplicate Finder and probably a few more. Any recommendations?

Manage your libraries OK, this one is a standalone app not a plug-in, but it is an incredibly useful tool for iPhoto users. Normally, you only have one iPhoto library for all of your photos.

iPhoto ’11 has built-in sharing support for Facebook and Flickr, but not Google’s Picasa service. With Picasa’s iPhoto plug-in, you can upload images to your Picasa galleries.

Cleaner Kit is an AI-powered storage-freeing app for iPhones that helps you get rid of the junk, like duplicate photos and marketing emails.