A group of app developers are working on ways to bridge the blue/green divide.

NEW YORK — If you send a text from an iPhone to another iPhone, most of the time that text is blue. If you send a text from an iPhone to an Android phone, that text is green.

On its surface, it may seem like no big deal, but behind those colorful messages is a years-long battle between Apple and a group of app developers working on ways to break down the blue/green divide.

The first text message was sent December 3, 1992. It was sent by software developer Neil Papworth to Richard Jarvis of Vodaphone, a British Telecom company. Jarvis was at his office holiday party at the time, so the message read simply “Merry Christmas.”

That holiday greeting was an SMS, also known as the short messaging service. SMS was a common technology that phone companies and software developers all agreed on: this was how texting was done.

“SMS is the protocol by which basically text messages have been sent for over a decade at this point,” says Chance Miller, the Editor-in-Chief of 9to5Mac.

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About ten years later, the Multimedia Messaging Service debuted, known as MMS. Now, texts could be longer, and users could send pictures and videos through text.

Then, in 2011, the texting paradigm shifted again when Apple introduced its proprietary texting app, iMessage.

“Apple billed iMessage as basically a modern take on SMS,” says Miller.

iMessage offered more than just simple messaging. “Read receipts” showed whether the recipient of a message opened a text. Typing indicators signified that someone is texting the user back. iMessage users could send and receive higher quality pictures and videos. Later, iMessage would add the ability to “react” to texts, adding another dimension to text communication.

iMessage texts also got a fresh coat of paint: outgoing texts now appeared blue. Texting an Android phone from your iPhone defaults back to the older SMS technology, which means no read receipts, no typing indicators, and no high-quality picture and video messaging. Instead of blue texts, outgoing texts to Android users were green.

“There’s a stigma associated with green bubbles,” says Miller.

Beyond the social implications of green or blue bubbles, there is also a privacy concern. Blue texts – iMessages – are encrypted. That’s not the case with SMS messages.

“The SMS standard has no built-in encryption whatsoever,” says Miller. “Your messages are vulnerable to your carrier seeing what you’re saying [or] somebody coming in and giving a warrant to Apple or your carrier and them having to hand over that information.”

In recent years, a cottage industry of developers has emerged, all working on ways to bring the “blue bubble” to Android communications. Earlier this year, Nothing Chats — an app made by Android smartphone manufacturer Nothing — purported to bring iMessage to Android. But Miller says that company used its own Mac computers to act as an intermediary between its users and the Apple devices they were texting, which raised security concerns.

“What you’re doing is basically handing over your Apple ID and your password to this company, who was then logging in on your behalf to basically a Mac in a server farm somewhere,” says Miller. “So you have no idea what they’re doing with your Apple ID and your password and it’s just not in any way shape or form a secure way of doing it.”

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Nothing voluntarily pulled the app from Google’s app store shortly after launch over those privacy issues. In a statement on its website, Nothing apologized and says it is working to “fix several bugs.”

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Earlier this month, another developer called Beeper launched an app called Beeper Mini.

“Android users can download this app, and it turns their messages from a green bubble into a blue bubble,” says Beeper co-founder Eric Migicovsky.

Unlike Nothing Chats, Beeper Mini doesn’t use a server farm of Apple computers. Instead, Migicovsky says they reverse-engineered iMessage.

“We looked at how iPhones connect to iMessage, and we reproduced the same technique on Android,” Migicovsky tells ABC Audio.

“They’ve found a way to spoof it and make it look like you’re an actual Apple device, even though you’re an Android signing in through Beeper,” says Miller.

Migicovsky says 100,000 people downloaded Beeper Mini in the days following its launch on December 5. Those who did had access to the world of iMessage, complete with most of its features – including encryption.

“We were getting messages from all over the world about people who could finally join the groupchat with their family,” says Migicovsky, adding, “we heard of people who had better success dating because they had a blue bubble versus a green bubble.”

But those blue bubble communications were short lived.

On December 8, Beeper Mini users began reporting their messages weren’t getting through, leaving communication limited to the older SMS standard. Amid the confusion, Apple weighed in, saying it “took steps to protect our users.”

“Three days after we launched, Apple attempted to block Beeper Mini,” Migicovsky says.

Apple’s statement didn’t mention Beeper by name, but went on to say it was “blocking techniques that exploit fake credentials in order to gain access to iMessage,” and that those techniques posed “significant risks to user security and privacy” — including leaving users open to “unwanted messages, spam, and phishing attacks.”

Migicovsky says that isn’t true.

“Beeper Mini definitively, provably, made communications between iPhone users and Android users more secure. They turned it from a green bubble to a blue bubble,” he says. “The actions that Apple took caused the opposite effect. They made communication between iPhones and Androids unencrypted — less secure.”

Miller says if Beeper Mini is exploiting a flaw in iMessage, then Apple is right to be concerned about privacy.

“Apple’s statement — it holds up in some ways,” says Miller. “Even if Beeper’s doing it for good, somebody else could come in and find that reverse engineered protocol, and take advantage of it for things like spam, phishing attacks, unwanted messages and all that.”

Migicovsky, for his part, says Beeper Mini is secure.

“We’ve proven time and time again that we’re good stewards of your trust, and have only built a secure and useful application,” he says.

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Beeper Mini is now back up and running, with some changes. Android users can still message iPhones with blue texts, but they need an Apple ID to do it. Earlier iterations only required a phone number to access iMessage.

“We’re still working on a full fix — fingers crossed,” says Migicovsky.

As pressure has been growing on Apple to make iMessage more accessible — SMS texting has been replaced by a new standard: the Rich Communication Service, or RCS.

“RCS, it does, in a lot of ways, what iMessage does with read receipts, typing indicators, high-quality pictures and videos — but it’s a standardized platform,” says Miller.

Most major Android developers have adopted the RCS standard, which means Android-to-Android texting now comes with many iMessage-style features, such as read receipts and encryption. Last month Apple announced it would support RCS starting in 2024, which means iPhone to Android text conversations could get those features in the new year. But Miller says while RCS may be poised to solve some of the technical problems with texting, one thing will remain the same.

“Apple has said RCS messages will still be green bubbles,” says Miller.

By Michael Dobuski