Found an Iphone 5; now what?

So i found an iphone 5 and l contacted the people in their phone and i talked to them and gave them my phone number so that they could contact me because the cell phone was dying and i don't know anyone that has the new charger for the phone. After they had my phone number they said they would contact me. I haven't heard anything from them days, and i have no way in getting contact with them. Now my friends have been telling me to keep it, Although that would get me money- I don't want to but at the same time I do. I did the right thing and gave them my number to tell them I had it. What should I do? And if do end up selling it, could i do it? (Aren't they going to report it lost- I'm assuming) Can I sell it if they report it lost to the phone carrier it was under?

Added (1). Oh btw, it doesn't have any important stuff when the phone was on- I checked through the phone to see the contacts- and it just had a few apps, its only 2 months old.

Added (2). Oh btw, it doesn't have any important stuff when the phone was on- I checked through the phone to see the contacts- and it just had a few apps, its only 2 months old.

Added (3). And why should i spend money (for a charger)? I'm currently taking my finals so i'm really focusing on that. I've asked people if they have a charger but noone has one! Plus, when i talked to the person on the iphone and gave them my number they didn't even say thank you or anything! They sounded hungover!

You should have brought it to the police.
If they didn't pick it up after one month, it would be yours.
You would get papers that its officially yours, incase you would want to sell it.
Your best bet is to wait a few weeks and after that keep it or sell it.

You did the right thing. What i suggest is that you find a charger for it if it has died… Call mom, dad, sis, babe, home… And find the owner, even if the people haven't called you!
you never know when you may lose your phone and someone goes out of his way to get it back to you!
Remember it is not just a phone it may have a lot of stuff on it which hasn't yet backed up and the owner is missing them… Like photos and important messages.

Find a charger for it, barrow a friends or even go to a five below/dollar store and they have chargers there. Contact them again. If they still don't get back at you after a month, it's yours. Congrats.

Put it up on craigslist, say something like, tell me the contacts and the color so your giving it to the right person. If no one claims it, i would just take it

Turn it over to the police, simply put it is the best thing and easiest thing to do.

You did the right thing which is more than many people would have done. You gave them your number, the rest is on them. If you really don't hear from them, you have a new iPhone.