Found an iPhone in the parking lot, can I use it myself?

I found an iPhone 4 without a SIM card. If my own SIM card from my own phone can fit, will I be able to use it? My current phone is not a smart phone, so if I used the internet on the iPhone, would I still be charged for it?

Well, what carrier is it? If you don't have a micro sim card, plug the iPhone into your computer, restore it, go to your AT&T, Verizon or Sprint Store, (depends on your carrier) ask them to figure out if its your carrier and ask for a micro sim card if its your carrier and also ask for them to set it up. Hope this helps!

Yes. But if you have att as your carrier it will add a data package to your account.att requires a data package for every smartphone. If you don't add one the system will add one for you.

Sure but, You forgot about the part where you try to return the lost or stolen phone to the original owner, Christmas spirit and all that right.

Your carrier will charge you with a data plan even if you don't use internet - they will know that you've got a smartphone and will tack data onto your bill. Obviously you would have to pay if you DID use the internet - why would you think otherwise? If it were that easy that would mean that millions of people are stupid for paying for data. Yes. You will be charged.

On another aspect of this, you will also be charged with theft if the cops find you with the phone. Your SIM in the card will make it easy for the prosecutors. Everybody takes cellphone theft seriously. Judges figure that if the word gets out that even first time offenders are going away for a few months, it will deter more would be thieves. They probably wouldn't be able to seriously touch you with your state's version of a theft charge, but possessing stolen property is a different matter altogether. It doesn't matter if you thought it was lost - you know it wasn't yours. (And don't bother trying to lie about it being a present from some guy you know from the street, or something you bought - nobody's buying that one).

Luckily the right thing is the smart thing. Give it to a cop.