I switched iPhones, do I have to rebuy an app I paid for?

So, I got a new iPhone, but I haven't put the SIM card in yet because I'm waiting tomorrow to go and get it put in.

Basically I'm using it without my SIM card in it.
I went to download all my apps, and it says I have to rebuy this one app I've already bought.

Do I actually have to repay? Or is there a trick to this?
Was I supposed to transfer it or something from my SIM card?

So confused.

I thinks its ok if you log in with the same Apple ID

You'll never have to buy an app twice as long as you have your iTunes info, I have the same apps on my iPod iPhone and iPad.

My understanding is that unless you have an app that lets you save your apps to your sd card, then you will have to download (and pay) for any replacement app.

That's why I only use free apps.

It'll say buy in the app store but once you input your password and it begins to download it will say you have already purchased that app therefore you won't be charged