The majority of the photo-viewing apps for the Apple iPhone and iPod Touch require you to first upload images to a service. The WD Photos app from Western Digital gets at your photos right where they live by remotely accessing your My Book World Edition network drive or WD ShareSpace network storage system. (You know, assuming you store your photos on one of those devices.)
The app takes advantage of MioNet, a remote access service integrated into the WD drives. After you've signed up for a free account, you just use the same log-in info for the app. Once logged on, you should see a list of network-connected drives attached to your MioNet account. Select the drive you want and you'll see thumbnails of the photos stored in the preconfigured Shared Pictures folder.
Tap a thumbnail and the image opens full screen. From there you can e-mail photos, assign one to a contact, start a slideshow, or save it to your device. The performance is pretty quick with a Wi-Fi connection, but still good with a strong 3G signal. Plus, once you've viewed a photo you're able to see it when you're offline. There are no options for fast posting to Facebook or Twitter, but you can always do that after a photo is saved on the iPhone or Touch.
If you already own an iPhone or iPod Touch and a Western Digital My Book World Edition and/or WD ShareSpace network drive, then the free app is a no-brainer. If you don't, maybe this is one more reason to buy one or the other.