TiPb Answers: How iMessage works [FAQ]

We're getting tons and tons of questions about iOS 5's new iMessage, how it works, where it sends to, and how to avoid sending to the wrong person or device. Apple hasn't given out a lot of details about it yet, but based on what they showed on the keynote and how they've previously handled user and device ID, we can make some guesses. Now if it looks a little complex... wellafter the break!

So here's how iMessage works, as best as we can figure out at the moment.

How do you enable iMessage?

You can enable iMessage in Settings on iPhone, iPod touch, and iPad. It's similar to how FaceTime is setup.

  1. Launch Settings
  2. Tap on Messages

(opens in new tab)
  1. Tap on Use Your Apple ID for iMessage
  2. Sign In with an Apple ID (MobileMe, iTunes, etc.) or Create New Account
  3. Enter the email address you want to use for iMessage
  4. Apple will verify the address, if it's not already registered, you'll get an email asking you to verify it.
  5. You can Add Another Email address, or several, if you want.

(opens in new tab)

If you're on an iPhone, once you're logged into iMessage your iPhone phone number will also be registered with iMessage and anything sent to it from another iOS 5 device will prioritize iMessage over SMS.

Does iMessage count as text or data?

  1. Messages SMS still count against your total number of SMS/MMS in your package (if you have a limit)
  2. iMessages are sent over data, not SMS/MMS so they count against your data cap (if you have one).

How does Message decide between sending SMS and iMessages?

When you enter a contact into Messages, you'll see all the available phone number and email accounts for that contact.

  1. If they have an iMessage-registered email address, you'll see a little blue word bubble to the right of the address.

(opens in new tab)
  1. If they have an iMessage-registered iPhone phone number (their iPhone is logged into iMessage), you'll see a little blue word bubble to the right of the address.

(opens in new tab)
  1. If they have a non-iMessage phone number (for example, they're logged out or they're using a BlackBerry), you won't see any bubble.

When you pick a contact, it starts off gray and Messages will process it for a second.

  1. If it determines it can send via iMessage, the contact turns blue and the text entry box says "iMessage".
  2. If it determines it can send via SMS/MMS, the contact turns green and the text entry box says "Text Message".
  3. If it determine it can't send via either iMessage or SMS/MMS, the contact turns red and shows an exclamation mark.

So which device sends what type of message then?

  1. If you're on an iPhone and all you have is the other person's mobile number, Messages will send via SMS
  2. If you're on an iPad or iPod touch and all you have is the other person's mobile number, Messages will not be able to send (you'll get a red exclamation mark in the contact name), because iPod touch and iPad can't do SMS.
  3. If you're on an iPhone, iPod touch, or iPad and all you have the other person's iMessages ID, Messages will send via iMessage

What if I have an iPod touch or iPad, but my phone is non-Apple? (Feature, BlackBerry, Android, etc.) Will my iOS device intercept my SMS?

No. Remember, when you enter in a contact, you can see all their associated numbers and email addresses.

  1. If the person sends to your iMessage email address, it will show up on your iPod touch or iPad.
  2. If the person sends to your mobile phone number, it will show up on your mobile phone.

If we share the same iTunes account, how do I make sure my husband/wife/kids don't get my iMessages

Luckily, Apple's fragmented ID system works in your favor. Just like FaceTime, iMessage email addresses are separate and independent from iTunes logins.

  1. Choose the same address for multiple devices if they're all yours and you want to get your iMessages on all of them.
  2. Choose different addresses for multiple devices if they belong to different members of the family and you want them each to get their own iMessages.

You can use any email account you validate with Apple (we even know some people using @crackberry.com accounts. Shh. No names.)

How do I see/change the address associated with iMessage?

  1. Launch Settings
  2. Tap Messages
  3. Scroll down and tap on Receive At
  4. Tap Add Another Email to add an addition email account
  5. Tap an existing email account, the tap Remove This Email to remove an account

Just go through each of your devices and assign them the same email, or different emails, as suits your individual or family needs.

Any other questions?

Again, we won't know for sure until iOS 5 ships this fall and Apple officially explains how iMessage works, but this is our best guesses based on available information. If you have any corrections, or other questions, let us know!

Rene Ritchie
Contributor

Rene Ritchie is one of the most respected Apple analysts in the business, reaching a combined audience of over 40 million readers a month. His YouTube channel, Vector, has over 90 thousand subscribers and 14 million views and his podcasts, including Debug, have been downloaded over 20 million times. He also regularly co-hosts MacBreak Weekly for the TWiT network and co-hosted CES Live! and Talk Mobile. Based in Montreal, Rene is a former director of product marketing, web developer, and graphic designer. He's authored several books and appeared on numerous television and radio segments to discuss Apple and the technology industry. When not working, he likes to cook, grapple, and spend time with his friends and family.

128 Comments
  • What is the definition of "iMessage-registered". For email addy's is it the address you select to receive messages? How do you go about registering a phone number?
  • This doesn't make sense.
    If they have an iMessage-registered iPhone phone number, you’ll see a little blue word bubble to the right of the address.
    That means iMessage will work if neither party has their e-mail associated with the contact?
    But then, you conflict yourself:
    If you’re on an iPhone and all you have is the other person’s mobile number, Messages will send via SMS
  • Their phone number will be registered with their iMessage account/appleId so you don't need to have the email address in the contact.
  • Screenshots to illustrate this text would be very helpful, thanks!
  • So if I have an iPhone and an iPad, how do I go about making sure all my iMessages appear on both devices?
  • You bring up an interesting point. If someone is close to going over their data limit but has unlimited texting on their plan, they might prefer to send texts rather than iMessages. Can you opt out of sending an iMessage and send a text instead even though you are sending the message to someone with an iPhone? Will they be upset with you if they don't have unlimited texts and they receive a text from you instead of an iMessage?
    Hmmm...Thorny issues.
  • You can turn iMessages off.
  • Thanks, Rene, I didn't know that. But I still wonder about the etiquette because some people will want to use texts because of unlimited texting on their plans and others will want to use iMessage because they have unlimited data.
  • It would just be the same as life before iMessages. The people with limited texts will spend texts messages and unlimited won't. same goes for data. as far as wanting one or the other because it benefits you, well that's life haha. Hope that helps. My guess is most people will use iMessage because it doesn't really use all that much data and being on WiFi to save data is an option while you have no alternative for sms conservation.
  • I agree, Rene, there are those who don't have texting plans who don't want any texts sent to them. And you're also right that iMessages won't use much data (unless you're attaching a document, photo or video to the message). It will be interesting to see how this plays out.
  • Apple still fails here.. i'm sorry! You still have to use your apple ID. With BBM is PIN so your not giving any personal details.. with this you are.
    I'm sticking with Liveprofile. Sorry Apple!
  • I'd rather give email address than pin. Way easier, and most of the time I already have someone's email address that is associated with their apple ID. I'm not going to give out my personal details to randoms I don't know.
  • My take is you want to talk with 50 million people. The whole point of iMessage is to have personal messages with your friends and family. Not strangers. Thats what myspace was for and thats why its dead.
  • Ah, OK. I have a question: Does my iPad have a separate ID from my iPhone, so I can send from (and receive on) each separately via iMessage -- or will an iMessage sent to me arrive on both devices simultaneously?
  • Looks like you can either associate both with the same email address, or with different email addresses.
  • How does it handle multiple reciprocates in the same message? Lets say a mix of iOS devices and non-iOS devices? Do the iOS devices get an iMessage and the non-iOS devices get an SMS version?
  • Probably just as you would think. Sends an iMessage to those with it, and an SMS to to those without it.
  • What, read the article?! Oh, OK, thanks. And I like that answer.
  • Does it somehow associate the phone#-registered address with the e-mail-registered address so that a conversation begun on the iPhone can continue seamlessly on the iPad.
  • does this work like bbm, can i send messages to people who are out of country who have an iphone/iDevice without getting charged any extra??
  • Yes, since it used data it does not matter where the recipient is. But if you are the sender, watch out for the extra charges when roaming.
  • Do you think there will be proper group chats for iMessage the same way it is handled in BBM or Whatsapp? Is this something that might be improved before beta period is over?
  • No there will not be, at least it's not in the beta. Rene and Crackberry Kevin did a video on it.
  • Correct
  • Thank you! Finally understand this. All this iMessage and iCloud stuff just confused me more and more...
  • How does group messaging work? Can you add other people in a ongoing groupchat chat? whats the limit?
  • Yes.
    The sky.
  • This is probably yet to be seen, but if I am logged into iMessages with the same address on both iPhone and iPad, when I read it on one, will it mark it as read on the other? Will the new notification system acknowledge it such?
  • yes.
  • Reading these comments and you guys don't read at ALL.
  • will imessage work with international phone numbers?
  • Yes, just make sure you use the entire phone number including the country code.
  • Suppose someone uses your email address for imessage will they text your messages Thats not good if someone can get your imessages?????
  • That's what passwords are for.
  • Funny thing, I received a reply from someone I don't have their contact info from, he was replying to my ex. I replied right away asking who it was and what was going on ... my ex was able to reply as well as if he were me!!! This has happened twice, last Sunday and Tuesday, 2 different people.
    I was hooked via his iTunes account, not sure if that has anything to do with it!!??
    I have unabled the imessage option!!
    Can anybody tell me why this happened?
    Not impressed!!
  • Can somone use your email address to get your imessages?
  • Ok , but how I can send my location ??
  • What happens while you are roaming and you turned off data and someone sents you an imesssage? I guess the otherone will just see that you did not receive the message? What happens if you turned off imessage does the bubble disappear on the the senders iphone and therefore he knows that he has to send an sms?
  • If you're data is off it will simply send as an SMS.
  • what if my ipad is on, and i'm