Have you ever heard of an iPhone or iPad app referred to as a "Universal" app? Have you ever wondered what that means?
The most simple explanation is that a universal app is an app that runs on both the iPhone/iPod Touch and the iPad. But it actually goes a little deeper than that. After all, the iPad can run any iPhone application in 'compatibility' mode, but they aren't considered 'universal' apps. Why not? Because a universal app is one that is specifically designed for both the iPhone and the larger screen on the iPad, which allows for more information or features to be packed into a single screen.
Is there a benefit to downloading a universal app?
One of the great features of the App Store is the ability to re-download apps you have purchased without the need to purchase them again. If you've purchased the app once, you can install it as much as you want. (These apps will have an "install" button rather than a "free" button or a price tag button.)
If you purchase a universal app, you can install it on both your iPhone/iPod Touch and your iPad without being charged twice. This makes universal apps very attractive, especially those that really take advantage of the iPad's extra screen space.