iSale mobile lets you create online auction drafts on the go. You can pick from among 222 iSale templates, write a description for your auction item, and set the starting price, auction duration, and category. When you’re back near your Mac (and the desktop version of iSale), you can transfer all that data via WLAN.
The iPhone app is free, but it requires iSale 5.5, which costs $40. (Equinux offers a trial version that lets you try out three free auctions.) iSale mobile works with both the iPhone and the iPod touch.
Other apps of interest that were recently added to the App Store include: