Apple recently changed the equations and so now, you can gift an app directly from your iPhone or iPad. It was possible in iOS 5.x but when Apple first launched iOS 6, that special feature was disabled for various reasons. (Click here for the iOS 7 version of this tutorial.)
That has been a crippling factor for a few of us who loved the easy way one can gift an app right from the iPhone. The reason was, app discovery happened on the iPhone much more than on iTunes on a desktop. Most of the time, people found apps on their mobile devices and the ability to “gift” the app right from the iPhone/iPad is a subtle but powerful feature.
Here's how to gift an app from your iPhone/iPad running iOS 6 or 6.0.1:
Step 1: Open the App Store and find the app you want to gift. Tap on it.
Step 2: Once the app screen loads in the App Store, tap on the arrow icon on top-right.
Step 3: The last option on the share screen is the Gift icon. Tap this.
Step 4: Enter the email of the person you want to gift.
Step 5: You can optionally choose the date (up to 90 days later)
Step 6: Select a theme for the gift email
Step 7: Confirm your purchase (verify details) and then tap on the “Buy Gift” option.
Here is a quick video tutorial that will show you how to gift paid app from iOS 6 App Store:
App users who occasionally stumble on amazing apps would find the gift option really useful. This feature would also be useful for app reviewers. But most importantly, I guess it's a strategically good time to introduce this feature.
You can also read about how Apple's web-based App Store and HTTP protocol lets it update such little updates easily without the user having to upgrade the iOS here.