Ubuntu has an App Store called Software Center like that you see on your Iphone. Using this application, you can see programs you installed and other programs you like using a simple interface. Here, you can add or remove programs instantly easily.
Or, there are alternatives that functions the same, having a web-based approach. You just select the apps you like then install it with one-click. Haven't tried this yet but I've seen this from other sites and works pretty well.