It's always refreshing to see something new for photo aficionados and PhotoScope (US$4.99) certainly meets that criteria.
PhotoScope gives you complete access to your Aperture and iPhoto libraries from any iOS hardware as long as all your devices are on the same WiFi network. To get things up and running, you download and run a free helper app for your Mac. Next, launch PhotoScope from iOS, and with a tap to select either iPhoto or Aperture libraries, you'll see your pictures arranged as they are on your Mac. All the albums and projects are named, and the metadata is also available to you.
Photos can be emailed in large or small versions as well as copied, saved to your iOS camera roll, printed or tweeted. Images can also be copied and then pasted into other apps. PhotoScope supports flags and ratings, so you can remotely tag your photos (Aperture only) from your iPhone or iPad.