Ebay auction ending and a user bids $1,500 on my iphone that was about to end on $550?

Is this most likely a little kid mad, or is this a trick or scam?

Scam

Do you understand how eBay works?

The bid shown is not necessarily the highest amount the current bidder has bid. It is simply one increment more than the previous high bid. It might be the amount shown, $550, or it might be $600 or $800 or even higher.

If someone else bids, they bid against that invisible bid. If they bid $1500, the only way you would know it is the previous bidder's hidden bid was $1500 too.

Do not do anything until he shows as Paid in your Ebay history. Normally these are either fake bidders or hacked accounts. Nobody is going to pay that much for an iPhone unless it's a scam or a fake bid