Another new feature of iOS 5 is called iMessage. It’s like texting but you can only message to others with the iMessage app. Currently only the iPhone, iPad and iPod touch run the iMessage service. It’s great because it’s a part of the current Messages or Texting app. For iPads and iPod touches, you’ll get a new app that wasn’t there before. For iPhones, It’s part of the same app used before for texting but won’t cost as a text through your carrier if both parties have iMessage. This will not work for regular phone numbers.
When using an iPhone, you can tell if you’re sending a text message or an iMessage based on what is displayed in the typing field before you type something. Here’s an example:
With iMessage, you can also see that the message has been delivered. See the previous screenshot again. You’ll see the word “delivered” under the message. You can also tell what type of message is being sent because the bubbles will be green for text and blue for iMessage and you can see when the other person is typing when a … appears.
A final tip to help you get it set up best: Go to you settings app, then Messages and scroll down to “Receive At” and make sure your email you want to use is listed. I had the word error next to my phone number and had to turn iMessage on and off again in the settings to get it to work again.