Just tap the home screen and hold it to create a folder. Now name the folder by taping it, then just drag and drop apps in it. To have a beautiful ICS like App folder on your older device, the best option is installing an ICS launcher app. Though, there are several ICS launcher available on Google Play Store, Holo launcher brings several ICS flavors to older android phone (android 2.2 and above) including App folder. Install the Holo launcher from Google Play and configure it from its settings menu. To group apps, just drag app on top of each other. You can also rename this app folder by taping it. If you are not like the launcher app, there are some apps specially designed to group apps as in ICS. For example, the App Folder that lets you customizes your home screen with folders like iPhone.
