Why does my Iphone keep saying not delivered?

So I'm texting 2 friends. One of them it won't send my text messages to even though I have service, yet it'll send messages to my other friend. I tried to send a text to some bogus phone number with not even enough numbers and it said it went through! I'm tired of trying to text them over in over just in case they are going through and I'm just not getting their replies. Why would it keep saying not delivered for some text messages to the same person but not the other person. Could it be their provider?

Is there an untethered jailbreak for iPhone 4 IOS 6?

All I can find is news articles claiming it will come out on the 22nd, and tethered versions. Is there one out yet?

IPhone 4S to 4? Different Carrier?

My iPhone 4S broke, and my sister gave me her old iPhone 4, which was for Verizon. It has no sim card slot, so if I go into the AT&T store, will they be able to put my service onto the iPhone 4? Or is it carrier specific?

Screen of my IPhone went black and now it won't turn on, what is wrong?

The screen on my IPhone 4 went black and now it won't turn back on. It didn't get wet or anything Please Help!

Added (1). It was fully charged when this happened AND when I plug in it will not even light up.

Should i get a iphone5 or galaxy s3?

I'm able to upgrade from my EVO to another phone and I jus want a phone that is fast, and have a good long lasting battery. So should I get the iPhone 5 or galaxy s3 and why?

IPhone 5 LTE not showing up after calls?

My iphone 5 gets LTE after I reset network settings, but everytime i answer a call LTE goes away and i have to reset network settings AGAIN if i want LTE back. >< Help

Tumblr won't let me log on

I've deleted the cookies and cache. I've tried Internet Explorer and Chrome. Nothing will work! And I can't use my phone cause it's so outdated and I can't update the app because of the shitty software. (I have an iPhone 3GS.) It sucks because I use Tumblr on a daily basis. I just wanna figure out what's wrong.

Looking for a cheap iPhone 5?

I use to have a iPhone 4 but it got stolen during the summer and then my dad cancelled the line. This year I'm looking forward to buying an iPhone 5 but with my own money. Anyone know where I can find a cheap one? I'm fine with a used or refurbished.

Added (1). I don't want to be a new member of a contracted company

Should i get the s3 or the iphone 5?

Still unsure which phone to get so do you have any insight?

1. How can advertisers use psychological appeals?

1. How can advertisers use psychological appeals?

2. What are Ogilvy's great advertising elements?

3. What's the purpose of the headline?

4. What is meant by "copy-style"?

5. What is the big idea? Give an example of a company that had a big idea. It does not have to be the iPhone, but an example of an idea that possibly generated a huge increase in sales.

6. What are the basic means of attracting attention?