My iPhone says there's no sim card installed but there's one?

My phone has been working fine but up till a couple days ago, a message popped up saying there wasn't a sim installed. I hadn't touched the sim card at all. I have been turning it off and on and its been my only solution but it keeps happening. Its getting pretty annoying so any ideas?

Why does find my iPhone need internet?

So i've had this burning question about these programs that are supposed to recover you're phone. From what I've seen they all require an internet connection so that they can send the request for the phones location, or to tell the phone to set off a siren or lock.

The problem is that, for me at least, I never leave my Data or Wi-Fi on when I'm not using them because they burn through the battery. So if i were to lose my phone it would most likely not have internet… At which point I would just be "up a creek without a paddle."

Why don't they just like communicate with cell towers like regular calls, or use text messaging, I'm sure there's some way they could rig it so that the their doesn't know you're locating the phone. Just so you could send the signal to the phone to let it know to start locating itself so it can send it's location back to you, or set of a siren etc.

is there some good reason they don't do this? Or do they do it and they just don't tell you… I'm confused.

How to turn off apps on iPhone 5?

I'm going to Italy for the next month, and I have a small data allowance (100 mb). I want to turn off some apps--log out of them so they don't use my data essentially. These include Tumblr, Snapchat, Twiter, and Instagram.

By just logging out of these, will they not use my data in the background? Is there a way to log out of the Snapchat app? Is there something else I can do to prevent these (but just certain apps) from not using data at all?

Why won't my music in itunes load when I log in?

I'm using my sisters laptop and would like to put my itunes on it. I logged out of her account and signed into mine, but her music still shows up and mine doesn't. How can I fix this so I can sync my iPhone with my music without losing anything?

Why Can't I Hear Anything When I Take A Video On My Iphone 4?

I was taking a video on my phone but when I tried playing it all I heard was an annoying high pitched noise. However, my Voice recorder does work. Its just the video. It also works when I have my headphones in. I researched the problem and found out its common on the iphone 4/4s. I tried doing the microphone cleaning that seemed to work for others but didn't for me. Is there anyway to fix this? Or any apps that will allow me to record video and hear it?

My iPhone 4s camera won't work?

Everytime I go onto my camera it's just black and nothing happens even when you try and switch from front to back camera! When I go onto camera it makes my whole phone freeze for a few seconds, especially when on snapchat! I'm going on holiday in 2 days so can someone please help me fix this as I will want to take pictures.

Ps. My phone screen has been replaced several times due to me dropping it and it smashing if that is the problem? And it's currently smashed and there's no glass over the front camera but the front camera is still there and works 1/100 times, same with the back!
I just want my phone back to normal please

What are some sterotypes of white American girls?

I'm an American, white, teen girl, with long blonde hair, I wear uggs, I wear pink, the brand pink, Hollister, American eagle, and what not. I have an iPhone, cracked the corner of the screen, and people say I'm a stereotypical white girl. And I would just like to know what are some stereotypes of white girls?

CAN YOU TAKE THE BACK OFF OF AN IPHONE?

SO, I'M WANTING TO SWITCH PHONES THROUGH STRAIGHT TALK. I HAVE AN IPHONE SMARTPHONE THAT I HAD GOTTEN FROM SPRINT AND WOULD LIKE TO SWITCH THE PHNE OVER TO THE STRAIGHT TALK ACCOUNT THAT I NOW HAVE. MY QUESTION IS IS THIS, CAN THE BACK COVER COME OFF OF THE IPHONE So THAT I CAN CHECK FOR THE SIM CARD?