Iphone 5 will not identify mobile SIM

I have just recently purchased an iphone 5 and have not even had the chance to properly use it. I have insterted three SIMs in the phone and the first SIM was recognised however it was an invalid SIM which was the carriers fault, not Apple's. However I put another three in there and the SOS only has stayed. I have blown into the SIM tray, reset my iphone 5 and gone to my mobile carriers if they could help but nothing has worked. How can I make it detect the SIM?

Why does my iphone 4S have to be charged daily?

I have a new iphone 4S and I have to charge the battery daily, I thought they held the charge a lot better then that. Is this normal? Games are played, but not for long periods of time and the internet is used also, I guess I'm using it more than I thought. Just wanted to be sure there isn't anything wrong with the battery. Has anyone else noticed this problem with theirs?

Is it safe to not put a case on my iphone 5?

I own a black iphone 5 and i don't really want a case on it. But i'm worried about it breaking or scratching. I go to highschool. It will be in my pocket all day. I may bump it on a bench every now and then. Is it safe to do this or is it better to be safe then sorry. No one in my school will hit it or anything the school isn't that bad.

Is this a scam (amazon.com)?

I'm selling my new iphone 5 16gb and this is what i got as a message from someone.

Her: I want to make purchase of your item but i would like to know the condition before i make purchase mail me back on amjphail at yahoocom

me: the condition is new.like, the wrapper isn't even off.

her: Thanks so much for being sincere, the item is for my colleague as a gift but she's currently on vacation so i want you to help me post it to her, i'll add $80 for the postage, send me the invoice of the total cost through PayPal to amjphail@yahoo.com so i can transfer the money as soon as possible.

IPhone 4 s OR Samsung Galaxy S3?

I'm getting a new phone but i'm not sure which one to choose between these 2! I have read lots of good reviews about the S3 but to tell the truth i'm not sure about android and how user friendly it is! So tell me what you think and why

Why is my AT&T iPhone 4 service so bad?

I have had my iPhone 4 for well over two years and lately I get absolutely no service wherever I go, is this a battery problem or what? My mom has the same phone she hasn't had it for as long but her iPhone 4 and her boyfriends iphone 4 work just fine. My service is just bad. And I need to figure out why.