iphone balloon message colors

Blue means the message was sent or received using iMessage.

Green means the message was a regular SMS text message.

Blue = iMessage

Green = non-iMessage

Currently, iMessage is only availble for iOS 5. So where you send text / photos / videos to someone who also has iOS 5 installed, the messages appear blue. Otherwise they are green.

This is very useful for knowing beforehand whether you'll be charged SMS/MMS fees, especially if you're messaging with someone in another country.

Learn more about iMessage here:

http://www.apple.com/iphone/built-in-apps/messages.html

What does grey mean?

thanks

I'm pretty sure the grey bubble means just their message. Sometimes you will get messages from your carrier, etc. and those messages will be grey as well.

What does grey mean?

thanks

ok now i get it thanks

Why would the balloons be sometimes blue & sometimes green to the same person?

We both have the iPhone 4.