Does screen protectors burn iphone 5/ipad mini screen?

I heard somewhere that screen protectors of any kind cause your screen to heat up and lose pixels over time and that there's no need for them anyway because keys and stuff can't scratch or harm your ipad/iphone screens in anyway anymore and new screens for ipad mini or iphone 5 are somehow scratch proof. Is it true?
So I'm kinda asking 2 question here.

Can I buy a locked iPhone for cheaper and pay a price to unlock it?

I know the question sounds a bit naive, but I don't understand much about iPhones.

Just to put in context: A family member from another country wants to buy an iPhone 5c in the US And use it there. I know there's an option to buy a factory unlocked phone, but it's kind of expensive.

I heard they're selling the iPhone 5c at Walmart for $45. Awesome, if it didn't come with a contract… However, I've hear of websites that unlock your phone for $25-$70.

I'm not sure if Walmart's offer expired or anything, however, being completely optimistic that would only cost my aunt 70$ to buy and use an unlocked iPhone in her home country?

Seems too good to be true.

Thanks, in advance!

Added (1). Thing is, Mr. AWESOME! She doesn't live in the US And that's not really my question.

How to set up an iPhone on 3 network pay as you go?

Just bought an iPhone 3G on 3 network pay as you go how do I set up mobile Internet and data etc the person I bought it off said I should just top up 10 pounds a month but I have no clue where to start as I've
Never used the 3 network? Cheers for help

Screenshot help, could it be fake?

My dad and my stepmum rented their house out and they evicted their tenants and now on of the tenants has sent me messages saying that my stepmum has said nasty things, really disgusting things about me, my son and my unborn baby. She sent me a screenshot that apparently my stepmum had wrote to her and it does have my stepmums number but I want to know if screenshots can be tampered with? I'm not sure what the phone is, I'm assuming it's an iPhone but as I said I don't know. If anyone knows if you can fake them or knows how to do it please let me know because it's very important.

IPhone 4S has weird lines across the screen

I have dropped my iphone on carpet and it landed on the case but now has weird blue, yellow sometimes red and white lines across the screen. Help? Will Apple replace it? Can I fix it? Is there a repair place that will fix it?

How to stop apps from updating iPhone 4S?

Today I hit "Update All" in the app store and suddenly remembered there are a few specific apps that I DO NOT want to update. I tried everything to get it to stop--turned off Wi-Fi, turned of 3G. And it DID stop. But I needed to turn back on Wi-Fi and 3G again, which would start the updates back up. But, at one point a couple of months ago, my phone was filled to the brim with photos, preventing any apps from updating. Each app would have a loading bar, but when I clicked it, it would tell me there was no space available and I would be able to open the app again. I decided that maybe I could fill up my phone with photos again so I could try this same method; but this time it's not working. I click the app, it tells me there's not enough space to update, but the loading bar remains there, making the app unusable. Does anyone know how to get apps in the process of loading back to normal? Thanks?

(P.S. I hope this question makes sense, I'm tired and I'm not sure if I've worded his correctly)