How do I use iPhone apps on my Macbook Pro?

Okay, so I have always wondered if there are any apps that are used regularly on iPhones that can be downloaded onto my Macbook Pro. I tried to find an answer to this and discovered this page http://support.apple.com/kb/HT2519?viewlocale=en_US&locale=en_US which explains there is a way to download previous purchased apps on the computer so I followed the steps and downloaded some. Now this may be a stupid question, but does this just mean that I can now transfer these apps onto another device from my macbook, or can I actually use these apps in some way on a large, macbook monitor. If so how do I do this, and if not- I think it would be a brilliant idea for apple to make this an option in the future!

Thanks for any help, I'm still working out some of the basics as a first time Mac user!