Iphone 4s says no service! D

Okay, so my iphone 4s says no service usually it says AT&T 4G and it shows the bar sign but today it didn't, this is my first time experiencing this complication. In the morning when i was in school, everything was fine and i used the internet to look for information about a book and in my biology class never has signal so sometimes my phone says no service but later on it continued to say no service, I looked at my friends iphone 4s and she has AT&T too and she had 4G. I tried everything i turned off my Wi-Fi then turned it back on, i turned off the cellular data and turn it back on, i put it on airplane mode then turned it off, it said it was searching but then it said no service. I've had this phone since april so its not that old. Although, my lock/power button is broken, i don't know how but when i pressed it, i was unable to. I can't call or text and i really need it for school. I'm going to take it to the AT&T store but for now is there anything I can do? Oh, also i can't reboot it because my lock button is broken and i'm scared to restore it because what if I need to turn on my iphone?

Best tablet to buy just to watch movies?

Looking at getting a tablet but the only reason I want one at all is to watch movies with it. Currently I use my iphone 4s to watch movies with can download them easy with itunes or rip them from dvd was thinking ipad mini but seems expensive at $300+ considering all I care about is being able to watch movies is there a better option? I like my iphone but the screen is just too small I like to watch movies while I do cardio at the gym or travel. The dedicated dvd players are too bulky though much cheaper just won't work with what I want to use it for.

What is the meaning of life?

I was bored today so I got my iphone and asked Siri "What is the meaning of life." unfortunately she was like "Would you like to do a web search for 'What is the meaning of life'?" I was lazy so I didn't feel like relying on Google for help… So.many.memories… Anyway! I still want to know. And guess what guys… The most detailed answer gets 5 points!

Does family mobile work with the iphone 4?

I'm getting an unlocked iPhone 4 and I have family mobile, and I was wondering if it would work? Also, I'm wondering if I got the microco sim card, how would I transfer all my info onto it or whatever… I just need somone to explain to me how it works, thank you.

How to check what network my iPhone 4 is on?

I bought it off a friend who didn't know what it was on either.
So i took it to a shop and the girl tried a few sims and said it was unlocked so i thought brilliant went and got a new sim (giffgaff) and then it didn't work, so i tried it in my friends phone (same as mine) and it worked fine!

i tried my girlfriends vodafone sim and it still didn't work!
How can i found out what network it is on! I know you can use the IMEI number i think, but dunno how.

Any answers would be good.

Iphone 4 Won't charge or show up in itunes?

I have an iphone 4 8gb that will not connect to itunes. I have a mac and I have the latest software for itunes. The phone will only charge with a a wall charger and will not show up in itunes. The phone screen just stays black and won't turn on. When i plug it into a wall charger it tells me to connect it to itunes.