iPhone: Is it possible to gift paid app to another user?
Yes, this is possible for Apps and music. For obvious reasons, you can only gift Apps that cost money. Unfortunately this is not possible with books from the iBook store.

From your Mac


Navigate to the App Store in iTunes
Find the app you want to gift
Click the little down arrow next to the "Buy App" button
A menu will appear, and one of the options is "Gift This App"




From your iDevice


Open the App Store app
Find the app you want to gift
Scroll to underneath the the screenshots
Tap the "Gift This App" button