App Genius, a new feature in iPhone 3.1, is a good way to find useful apps. Go to the App Store app on your iPhone or iPod touch (the latter will need to be connected to the Internet via WiFi), and click on the Genius tab at the top right. Once you’ve enabled this feature by following the onscreen prompts, it will then show your apps and for each one will recommend a similar app. Like iTunes, the Genius function works by pooling the preferences of all those using the Genius function. I have the AP News app on my device, and Genius detected that other users who have this app installed also have the Reuters app installed, so it suggested that. That was a good suggestion, as was Simple Web Search based on my having Wikipanion installed. But for the Dictionary.com app, it recommended Japanese Phrases. Nope, that’s not me. And another recommendation based on Wikipanion was the Declaration of Independence for iPhone and iPod touch. Not sure what the relationship is there.