The latest version of Apple’s iOS18 introduced several features that impact the inbox. Rolled out on January 28th and now auto-updating for users, these changes may affect how your brand’s emails are received and engaged with. With nearly half of all emails read in Apple Mail, marketers who rely on email performance insights to drive strategy are raising critical concerns. But while these changes present new challenges, they also offer opportunities for brands to refine their email strategies and continue engaging customers effectively.
At Wunderkind, we’ve conducted a deep dive into these changes, analyzing trends across our extensive client base to understand their full impact. As a leader in performance marketing, we know that success in email marketing isn’t about resisting change—it’s about adapting. With the right strategies in place, brands can continue to drive meaningful engagement, even in the face of evolving inbox experiences.
The Biggest iOS18 Email Changes
1. AI-Generated Email Summaries
Apple Mail now generates concise AI summaries of email content, replacing the traditional pre-header text. This means marketers no longer have full control over the preview text users see, making it more important than ever to craft compelling subject lines and opening text.
2. Redesigned Inbox with Categorized Tabs
Apple Mail now categorizes emails into four tabs:
- Primary (personal emails)
- Transactions (receipts, confirmations)
- Updates (news, newsletters)
- Promotions (marketing emails, often including Wunderkind-triggered messages)
Most marketing emails land in the Promotions tab, potentially leading to lower engagement since users may check this tab less frequently than their Primary inbox.
3. Digest View & Multi Auto-Opens
Emails from the same sender are now grouped together, prioritizing the first received email over newer ones. This update has led to a 23% increase in multi auto-opens (three or more simultaneous auto-opens on iOS devices, often referred to as “bot opens”) since December 2024 for some businesses. While this change artificially inflates open rates, it also reinforces the importance of optimizing subject lines and content for maximum impact.
How These Changes Impact Engagement Metrics
Across Wunderkind’s client base, we’ve seen a clear impact on engagement metrics. Open rates have become increasingly unreliable due to auto-opens caused by grouped emails, making it difficult to gauge genuine user interest. Many of these open events are triggered by Apple Mail rather than actual user engagement. As a result, click-to-open rates have declined, since the denominator (opens) has artificially increased due to these auto-opens.
Additionally, click-to-send rates have also decreased for some brands, signaling a genuine drop in user engagement as a result of these Apple updates. Since December 2024, clicks on auto-opened emails have dropped by 16%, and the overall click rate (clicks over sends) has declined by up to 20% since January 2025. This decrease suggests that users are interacting with emails less frequently as a result of the grouped send functionality, which limits visibility for newer emails in a thread.
While these shifts present new challenges, they also provide an opportunity for brands to rethink their email strategies. By using data-driven insights and making smart adjustments, brands can continue to drive strong engagement and performance.
What Marketers Should Do to Adapt
1. Prioritize Strong Subject Lines & Concise Copy
With Apple’s AI-generated summaries replacing pre-headers, your subject line and opening text must work harder to grab attention. Focus on:
- Clear, compelling messaging that aligns with your campaign’s goal.
- Avoiding unnecessary distractions or conflicting offers, ensuring the main message remains consistent throughout the email.
- Ensure your content sounds like it’s coming from a human! Limit use of emojis and ensure no more than 40% of the email body is image-based.
2. Optimize for Inbox Categorization
Since most marketing emails are now in the Promotions tab, improving inbox placement is critical. To enhance deliverability and engagement:
- Use Wunderkind’s behavior-based segmentation to personalize emails.
- Test into plaintext emails to diversify content.
- Optimize for mobile, ensuring emails are easy to read and interact with across all devices.
3. A/B Test & Monitor Key Metrics
With traditional open rates becoming unreliable, focus on:
- Click-to-send rates and conversion rates as better indicators of genuine engagement.
- A/B testing different subject lines, CTAs, and email formats to see what drives real user action.
- Tracking engagement trends over time rather than relying on short-term fluctuations.
The Ongoing Impact of iOS 18 & Future Considerations
Apple’s iOS 18 update is just one step in a broader evolution of how inboxes and email engagement function. As Apple continues to refine its updates, we may see further adjustments that impact how brands reach and engage their audiences. At Wunderkind, we are continuously monitoring these shifts, reassessing best practices, and adapting strategies to ensure brands stay ahead. Flexibility will be key as we navigate these changes together.
The key takeaway? Email marketing is still an incredibly powerful tool—when done right. Wunderkind’s expertise and data-driven approach ensure that brands don’t just keep up with changes but thrive in them. If you’re looking for a trusted partner to help you navigate the evolving email marketing landscape, we’re here to help.
Want to learn how Wunderkind can optimize your email strategy? Get in touch with us today!