The most exciting new feature of the new iPhone is the front-facing camera, making it possible to make video calls with Apple's new app, FaceTime. But that's just the beginning. The new hardware opens up a wealth of possibilities for innovative apps.
There are plenty of photo booth apps available now, but none let you frame up your own pictures as you're looking at yourself like you can in a real photo booth. Since the iPhone 4 now lets you see yourself when you're taking pictures, you can use its picture-in-picture display to point it precisely at yourself and your friends. This app could be engineered to take four (or dozens) of pictures in rapid succession in that familiar photo-booth strip format. Extra credit if it can execute a quick upload to your favorite photo-sharing or social-media site.
Augmented Reality Mirror
The app 'stachetastic takes a photo or grabs one from your library, then affixes a realistic-looking mustache, facial hair or hilarious features on top. Now imagine it in real time, seeing yourself with a mustache, crazy hairstyles, surrounded by bleeding zombies, enveloped in the flames of hell — you name it. Your reality can be augmented, with you in the middle of it. Or, you can hold up an advertisement to the front of your iPhone 4 (just like you can with a webcam now) and see all kinds of interactive 3D graphics embedded within the ad. The possibilities are endless.
Videoconferencing Over 3G
Apple primed the pump with its FaceTime videoconferencing app, but there's a catch. You can only talk between two iPhone 4 phones, and only over Wi-Fi. Let's take it beyond that, porting the excellent Skype webcam app to the iPhone 4, giving you the ability to use your choice of Wi-Fi or 3G to do your interactive video magic. Those who've opted for one of the cheaper limited AT&T data plans and want to videoconference over 3G need not apply, but with an unlimited plan you could be in business. A drawback: bandwidth-stingy AT&T would probably try to bar this app from the App Store.
The front-facing camera enables the phone to become a completely self-contained speech-recording device. Type what you plan to say, import it into iTeleprompter, and then use the iPhone 4's front-facing VGA camera to record or stream the video of your speech. Such an app could even have built-in speech recognition so the scrolling text would automatically keep up with your reading speed. It would be really useful for journalists on location. iTeleprompter could also come in handy if you need to place your notes in front of you as you make that all-important video conference call.
Now when you place your iPhone 4 on its dock, it can sit there innocently while surreptitiously recording video. All the footage could be digitally captured, sent up to a Web server, and recorded or observed live by you. With an accessory, the app could be equipped with a motion-activated recording and alarm, notifying you via text message if it detects anything in your iPhone's field of view.
Live Poker App
One of the features missing from online poker games is the ability to see the faces of your opponents, picking up on that "tell" that lots of weak poker players can't seem to conceal. iPokerFace rewards those who know how to control their emotions and show a straight face no matter what's happening with that poker hand, and penalizes those tenderfeet who can't seem to conceal anything. Tap any of your opponents' avatars, and you can see their current facial expressions, shot live by the front-facing camera.