I understand iCloud connects all your apple products together.
What I want to know is if I were to download an app on my ipad that costs money, the same app will automatically download on my iPhone....through iCloud, will I be charged twice for this?
You don't need to synch any more with iCloud - you just go to purchased apps, log in and you can download them to whichever thingy you want to (well, that's how I am doing it but I could talking out of my backside).
Apps are stored in your iTunes account so as long as you can log in to your device which runs Apple OS (ie not a wndows PC) they are free on the other devices if purchased. You dont pay twice.
iCloud is where your device OS, installed Apps and data are backed up to automatically unless you opt to switch it off. Like a Windows System Restore.
There always seems to be a bit confusion between iTunes account details and iCloud account details.
Hope that helps