I can't get Internet on my iPhone

I have just got a second hand iPhone 4S it's not that old. My sister has set up my phone to my home Internet so that when I'm at home I don't have to pay for my Internet and I have always got it. Well sometimes when I'm at home I can't get Internet why is that. Also when I go out side it can be any where I can never ever get Internet and my crap Vodafone £60 phone can get Internet when I go out and yes I have got credit I have brought a £10 pack for my phone that includes the web btw I'm on pay as you go. All my friends that have the iPhone can get on the Internet when there out why can't I we can be in the same room and they can get on the Internet mad I can't I don't understand why I can't please help me.

Looking for exact dimensions of iPhone 5?

I know the screen is 4 inches diagonally but how tall & wide is it? Also what is the diameter of the home button? Please give answers as accurate as possible in millimeters or inches. Any other specs would be helpful also, thank you!

How long did it take for you to get your iPhone 5?

I ordered mine three weeks ago from AT&T. They said it'd take 4-6 weeks for it to come but I have a feeling it's going to take longer than that.

I checked the order status on AT&T and it says it's still processing…

Should i buy iPhone 1G or 2G?

I really love iphones but buying a new one is out of the question.
I was thinking about buying a used iphone from ebay. Don't want to spend more than 100£ so i was thinking about buying an iphone 1g or 2g. So yea should i buy it or would they not support alot of apps? Or would they be slow and laggy? TX

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As I will still have all the apps I use on my iPhone but on the note and bigger screen as well as I watch a lot of videos online and it looks a lot better as well and will be cheaper to fix as well any other pros of switching and cons?

Amazon shipping from hong kong?

I ordered 3 iphone cases, not realizing they were coming from hong kong. I ordered them October 12th, they said their shipping a few days after, but it said estimated delivery will be November 7-28. Why does it take this long?

How to get pictures made from your iphone?

I have an iphone 4s {if that helps?} aha.
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