If you buy an app at the time it is free, and the price changes, then you still don't have to buy the app for the change in price.
Theft.
You don't buy it, it's a free app.
Yes it is free after you have paid
No, the messaging app comes free with iOS 5.0
its free you buy it at the app store.
Yes, but it doesn't just give the app to you. First, you have to through and buy the app yourself, and then they will refund you the app's cost.
Yes, if you buy it again with the same itunes account used to previously purchase the app, you can get it back for free.
If it is not a free app of course you do.
An app that you don't have to buy, so its free. You buy video games on it, some are free and some aren't.
If you buy an app that works on both devices from the app store, you can download for the other device for free.
You'll have to buy the facebook app for free in the app store or you can get on facebook in safari but an app is recommended.