Mailbox Provider AI: Apple Intelligence

Mailbox Provider AI: Apple Intelligence

As a deliverability consultant, I spend a good deal of time easing my clients away from the edge of panic. In the wake of Apple Mail Privacy Protection (MPP)  in 2021, consultation calls became therapy sessions with marketers struggling to break up with their open data and move on to more meaningful engagement signals. Then there was that wave of click-baity articles that came out after Apple MPP that “introduced” Gmail image caching as if it hadn’t been around since 2013. And if one more person asks me how to prevent their marketing emails from landing in Gmail’s Promotions tab (and now Apple tabs!), I’ll be tempted to hang up my proverbial hat and leave up a permanent out-of-office message that simply states the Promotions folder is the inbox.

But sometimes the opposite happens: some new technology gets introduced to the email landscape, and senders aren’t talking about or testing it enough. This is the case, I think, with mailbox provider AI technologies. Our industry is abuzz with excitement about how AI tools can make copy writing easier, streamline workflows, and generally optimize email programs to make them smarter, more personalized, and more dynamic. But marketers aren’t the only ones harnessing the power of AI to make the email experience better for recipients.

Over the next few weeks, I’ll be deep diving into the topic of mailbox provider AI. Apple, Gmail, and Yahoo are all currently employing AI, and each technology affects your promotional mail differently and requires that you take action to protect your brand’s voice and presentation in the inbox. We’ll go through each technology separately and highlight who in your audience is seeing this AI at work in their inboxes today.

In today’s installment, let’s take a look at Apple Intelligence.

Apple Intelligence: Who is currently using it?

The good news about Apple Intelligence is that, while it promises to pose significant challenges to marketers, the technology isn’t super widely used yet. Because of its processing power needs, it’s only available for people with iOS 18+ on iPhone 15 Pro, 15 Pro Max, and iPhone 16. That said, FirstPost recently reported that 76% of iPhone users with phones released in the past 4 years have updated to iOS18, and they speculate that the Apple Intelligence tools are a major driver of high iOS 18 adoption rates. Apple Intelligence features are now enabled by default on new phones for users that update to iOS 18.3. While the vast majority of your audience is unlikely to be using Apple Intelligence now, the reach of these tools will be growing, so take some time in 2025 to measure impact, test, and plan for adjustments.

Apple Intelligence changes the appearance of your email both in the pre-open inbox view, and in the post-open view of your email. Let’s take a look at how it works.

Apple Intelligence: Pre-Open AI Summaries

Simply put, pre-open summaries are replacing, confusing, or in some cases adding on to your preheader text. To get a better understanding of what this means, let’s take a look at how one email appeared in an iCloud inbox before and after Apple Intelligence was turned on:

(Before Apple Intelligence was enabled)

(After Apple Intelligence was enabled)

In the first version we see a nice play between subject line and preview text, and the reader is enticed to open the email to get the 15% off code. In the second version, the preview text is elaborated on by the AI summary, and the discount code is actually exposed right in the preview. It’s totally possible in this scenario that someone might bypass the email altogether, navigating to bg.com and inputting the discount code without ever having taken any action that associates the resulting sale to the email. You can see how this poses a problem for email teams: with goodies like discount codes being pulled into the inbox preview automatically, there is an increased risk of email attribution error.

In other scenarios, important details that you strategically placed in the preview text may be completely ignored by Apple Intelligence. Check out Fat Quarter’s preview text that calls attention to savings of up to 65%, an important detail if you’re trying to inspire recipients to open:

After Apple Intelligence was enabled, the inbox preview mentions the flash sale, yes, but leaves out details about just how good the flash sale will be:

On top of erasing brand voice in the inbox preview and posing a risk to email engagement and attribution, the pre-open summaries also change the harmonious relationship between subject and preheader text. The Oracle Digital Experience Agency recently did some testing and found that how Apple Intelligence treats pre-header text is inconsistent and unpredictable. So while preheader text has long been a way to creatively and playfully “finish the thought” of a mysterious or funny subject line, going forward you’ll have to assume you can’t rely on these 1-2-punch combos for your Apple Intelligence users. Of course you’ll still want to use all your creative juices to craft eye-catching subject lines for your wider audience, but subject lines should be to the point and be able to relay important information even if preheader text is absent.

Apple Intelligence: Post-Open AI Summaries and Inbox Monster Testing

Once an email is opened, a recipient can click the “summarize” button from inside the email and a summary, usually around 1 - 3 sentences long, will appear above the content, pushing more of it below the fold. Check out the example below:

(Email before “Summarize” was clicked)

(Email after “Summarize” was clicked)

Because post-open summaries require the recipient to click to view, we don’t think this part of the technology will have as big of an impact on marketers as the pre-open summaries. But you should test your email content to see if Apple Intelligence summaries push important content below the fold, and to test how Apple will summarize your email content. The internet is already filling up with hilarious and confusing examples of AI summaries gone wrong. While we think the post-open summaries are generally better than notification summaries, there are important design aspects of your email you can tweak in order to get a summary that better reflects your email’s intentions.

We have been hearing a lot about how email design can impact Apple Intelligence post-open summaries, so we teamed up with Inbox Monster to test some of the leading theories ourselves. Inbox Monster recently updated their Creative Projects tool to include an iPhone 16 AI view that will allow you to check out Apple’s post-open AI summaries before you send. 

Our testing approach was to take a single, simple email and code it a few different ways to see how Apple Intelligence summarized each version. The only thing that remained consistent across versions was the subject line: “Your first creative project is in.” Check out the email content kindly provided by Inbox Monster:

Now let’s walk through some testing scenarios, our results, and what those results might mean for your email design teams.

Hypothesis 1: Image-only emails are even more of a big no-no now with Apple Intelligence at play, because Apple Intelligence summaries ignore graphical text on images.

Version: This email version was created as one big image with no live text and no alt text.

Inbox Monster AI summary preview:

Result: In this version of the email, none of the graphical text was pulled in to help summarize the email. It seems that the summary relied exclusively on the subject line. This is a bit of a bummer because the recipient can already see the subject line, so the AI summary didn’t add any additional context.

What it means: If you previously used image heavy design, you’ll want to start thinking about ways to sprinkle more live text into your emails so that key points of your email are picked up in the summary.

Hypothesis 2: Apple Intelligence also ignores alt text on images.

Version: This email version was created with the same image as above with no live text, but with the following super descriptive alt text: "With your first creative project and rendering test, you now have some great insights on how your email shows up, plus a wealth of other collaboration and diagnostic tools."

Inbox Monster AI summary preview:

Result: All the beautiful alt text was ignored! Somehow this version’s summary ended up sounding even more dry and robotic.

What it means: You should always use alt text on images for many reasons. But as others have pointed out, and our own testing confirms, Apple Intelligence will not pull it into any summaries. This means you need to ensure that the most important parts of your email are coded with live text.

Hypothesis 3: The more live text there is, the more descriptive the Apple Intelligence summary will be. 

Version: Our third test was meant to produce the best results, and it delivered! This email was a balanced mix of live text and images.

Inbox Monster AI summary preview:

Result: We finally have a version of the summary that pulls out the most important information from the email. It’s interesting to note, too, that Apple Intelligence seems to be first prioritizing the subject line, then whatever live text is closest to the top in the email.

What it means: Keep your subject lines clear and informative, and make sure the calls to action and most important elements of the email are in live text. Place the most critical information close to the top of the email if you want it pulled into the summary.

Hypothesis 4: Apple Intelligence will probably ignore emojis since it doesn’t care about images.  

Version: We threw in a bonus test that was coded just like the previous (third) version, but added a few emojis to see if it significantly changed the summary.

Inbox Monster AI summary preview: 

Result: Emojis didn’t significantly alter the summary text.

What it means: Laura Sullivan from Inbox Monster had the brilliant idea to test emojis, because as she put it, emojis “may still be a great tactic for expressing ideas or emotion without interfering with the summary.” I love that we confirmed that emojis don’t disrupt the summary because if we can no longer rely on preheader text being paired with a subject line, we can at least still convey emotion directly in the subject line. Emojis of course aren’t right for every brand or content type, but it seems like using them strategically for more playful campaigns is still on the table. 

Laura further points out that the email we tested “benefits from having only two distinct content areas and one main call to action. This seemed to allow the preview to be directionally accurate in most cases. I have seen emails with three or more calls to action bring up AI summaries that are close to jibberish. My lesson here is to keep emails to one strong action.”

Want to run some tests of your own? We highly recommend Inbox Monster for all of your Apple Intelligence testing needs, and for so much more! Inbox Monster offers a comprehensive suite of deliverability tools, including design rendering, inbox placement testing, blocklist and reputation monitoring, spam trap activity tracking, and DMARC reporting. Request a demo here!

Apple Intelligence: Closing Thoughts

Aside from all of the design nightmares, I think the most concerning thing about Apple Intelligence is that it will summarize your emails by default before a recipient opens your email. This could ultimately lead to a decrease in email engagement. You can no longer entice recipients to open with vague or coy copy: Apple Intelligence is going to put all your email goodies on blast. You may have audience members who are active in the sense that they skim through inbox AI summaries of your emails just waiting for the perfect deal to come at the perfect moment, but you’ll never know it based on your email data alone. Apple Intelligence will have an impact on how people engage with commercial emails, and it underscores the importance of regularly asking your audience if they want to continue receiving promotional emails from you.