Normally, when asking a question we post what we have tried, potentially some code and results.
Now though from your question it looks like you are largely looking for a list of the apps, and likely a ability to open them. And it looks like you already have your cube and on click effect, so you largely need the list I imagine.
Googling around I could find a couple of resources, How to get installed apps list with Unity3D? helps you to figure out how to get a list from the package manager.
http://answers.unity3d.com/questions/627703/detect-if-app-is-installed-on-android.html helps you to figure how to launch the list while having the package manager class.
These same actions to be done in android studio can be found at How to get a list of installed android applications and pick one to run and Launch an application from another application on Android respectively.
Hope this helps a bit in your goal.