I lived in New York City during the late 1990s and early Aughts, which is to say I lived in New York City at a time that predated the iPhone. I returned to New York last week and could not believe how different the city felt as the majority of pedestrians were walking around staring at or tapping on their phones. Eye contact was never something found in abundance in New York, but last week I felt as though I were surrounded by the (briskly) walking dead while ambling about the city, except instead of coming after my brains, these zombies wanted only sidewalk space and the right not to yield to any oncoming foot traffic.
The behavior of pedestrian traffic in New York and other major metropolises may help explain how an app such as Type and Walk (paid), called Type While You Walk Free for the free version, can make its way onto the top charts. (It's currently third on the Top Free Apps chart.) You will either view this app as a helpful tool for your modern way of life, or as a harbinger of the end of humanity. If the former, please keep reading.

What Type and Walk does is provide a camera mode, but instead of snapping a photo, the app provides a keyboard and as you type, the words show up on the camera view. The app is more effective if you maintain good posture while texting or typing on your phone instead of pointing your phone down at your feet as you furiously tap out a message. Also, this app will be worthwhile only for long texts or e-mails of moderate length.
Once you have completed your missive, you can share the text by tapping on the share button in the upper-right corner, selecting Share from the menu, and then choosing Message, Mail, Twitter, or Facebook. The app you select will open with the text already copied, which saves you the step of having to paste it in. Still, it takes three taps to get the text out of the app and into another. There is also an option to copy text to your clipboard. Lastly, text entered in the app is automatically saved, so you can close the app and return to an e-mail or text that you have in progress.
From the Share menu, you can also choose one of seven colors for the text to prevent it from blending into the background.
On the developer's Web site, it says the app works in landscape mode with a bigger keyboard for faster, two-thumb typing. In my experience on an iPhone 4 (bear with me, I'm eligible for an upgrade in less than two months), the app did not support landscape mode, which is a severe drawback for any text-entry app. I upgraded to the paid app after testing out the ad-supported free app in hopes I'd gain landscape typing while jettisoning the ads. Sadly, I was left with an ad-free but portrait-only app for my 99 cents. Thus, my advice is to use the free version or simply separate the task of typing from the task of walking.