What to do with iphone before selling?

I want to sell my old iphone but I'm not sure what to do with it first. I've reset the whole device to factory settings, but is that all I need to do? I've already got a new phone with my number. I'm just curious as to what will happen when the new owner turns it on. Will they just have to set up their phone number to the phone? I hope I will not still be paying for the phones data when they turn it on…
Any advice?

Wi-Fi for iPhone 4S blurred out?

I'm just causally using my phone and I noticed Wi-Fi isn't on. I go to turn it back on and bam it's blurred out. I turned off my phone and even hard reset it when you hold the power and home button. If I back up my iphone to my computer and factory reset it to brand new will it start working again?

Do I have to disconnect my iphone from Verizon before switching to Straight Talk?

I want to get off my father's plan because he likes to use the fact he pays for it against me sometimes and I'm getting tired of it. So my question is, do I have to have him talk to Verizon (which I really want to avoid…) to disconnect my line, or can I just remove the sim from my iphone and put a straight talk one in?

How to restart Clash Of Clans?

So, I completely screwed up my first Clash Of Clans account on my iPhone. I restarted on my iPad and I'm happy with that account, but I want to restart on my iPhone. It keeps pulling up my old game no matter what I do. Is it possible to make a new game with the latest update?

How to survive socially sans a cellphone, blu-ray player, iPod, iPhone?

I'm a old-lady in the shape of a girl who is almost 30 when is comes to technology. I don't mind texting but I really dislike social networking sites, Facebook, Twitter, MySpace. I also sometimes get annoyed about how much technology has changed about ipones, iPods, Blu-ray I find they make people lose their identity and there's less face-to-face time. Because for thousands and thousands of years people didn't ride cars, listen to the radio, no electricity. And people survived ok. But now there's much technology people don't even care how pollution wrecking their damn own planet and cellphones give cancer. Besides most of Africa has starving people who have no technology at all and people should try to spend money on helping starving people. 'i'm finding it increasingly hard to maintain a social life without my smartphone though. It's like if you don't play ball, you're not invited to the game with some people. I find some people will not continue to talk to me unless they have texting as a communication platform. Should I just accept that I will be somewhat of a loner for the rest of my life because of my distaste for technology?

Can I Use a h20 on an at&t iPhone 5c?

I want to buy an iPhone 5c from eBay.
But their all to expensive but i found an at&t iPhone 5c and i was wondering if i can use it around the world like at Yemen without an at&t sim card?
And does it have to be Unlocked? And how much will it be to Unlock it and where?

Device already associated with an Apple ID?

I recently had had my sister sign in to her apple id on my iPhone, i downloaded a few songs, and then signed back into my ID. But now, multiple songs of mine are set for iCloud download. But, when i click to download them back, it comes up with a warning stating "This device is already associated with an apple id. If you download past purchases with your apple id, you can't auto-download or download past purchases with a different apple ID for 90 days" And it gives me the option to cancel, or transfer. If I click transfer will it delete my songs, or what would happen?