I found an iphone 4s from sprint and i want to cancel the data plan to my data plan?

What are the ways to do it for the owner of the phone doesn't know about?

The right thing to do is to try and return it.iphones are cool, but someone is probably upset that they lost it. I would take it to where ever you found it, and give it to a store clerk, or look for a Mom or Dad or grandparent.

Something will happen to the phone if you keep it. I found a phone in a store once, and it worked and everything! I brought it home and was playing with it, and now in don't work.

They can call and have it deactivated then the phone won't work.