Impact of iOS 15 Update On Open Tracking

Bird

9 Jun 2021

Email

1 min read

Impact of iOS 15 Update On Open Tracking

Key Takeaways

    • Apple’s Mail Privacy Protection (MPP) introduces major changes to email tracking on iOS 15, iPadOS 15, and macOS Monterey by blocking invisible pixels, preventing open tracking, and masking user IPs.

    • MPP preloads email images through Apple’s proxy servers — even if the user never opens the email — generating false opens that cannot be distinguished from real ones.

    • The feature activates only when recipients use the Apple Mail app (not Gmail, Outlook, etc.) on an iOS 15+ or macOS Monterey device and choose “Protect Mail Activity.”

    • This change affects all email services (Gmail, Yahoo, custom domains, etc.) if the user views mail inside the Apple Mail client.

    • Click tracking appears largely unaffected — Apple does not modify URLs, query parameters, or user-agent strings in testing.

    • Apple’s broader iCloud Private Relay masks IP addresses during Safari browsing, but click tracking from email remains accurately measurable.

    • With ~38% of global opens coming from Apple Mail clients, this represents a meaningful shift in email analytics.

    • Open rates will inflate significantly and become unreliable for: list hygiene, re-engagement workflows, segmentation, and subject line A/B testing.

    • Optimization tools dependent on opens — such as send-time optimization and open-time dynamic content — will no longer work reliably for Apple Mail users.

    • Deliverability strategies that rely on opens as a leading engagement signal will need to shift toward clicks and deeper engagement events.

    • Dynamic elements relying on real-time context (e.g., weather, countdown timers, device-based app-store badges) may break due to Apple’s caching behavior.

    • Bird products are already adapting to the change, with ongoing updates to ensure marketers can pivot to more reliable engagement metrics.

Q&A Highlights

  • What is Apple’s Mail Privacy Protection?

    A feature that blocks tracking pixels, hides user IPs, and preloads email images to prevent accurate open tracking.

  • When does MPP launch?

    Expected between September and November of its announcement year, aligned with iOS 15 and macOS Monterey releases.

  • How will users enable or disable MPP?

    When opening Apple Mail for the first time on iOS 15+, users are prompted to choose “Protect Mail Activity.”

  • Does the email provider (Gmail/Yahoo/etc.) affect tracking?

    No — the mail client matters. If opened in Apple Mail, MPP applies regardless of the mailbox provider.

  • Will Gmail app users on iOS be impacted?

    No. MPP only activates when using Apple’s Mail app, not third-party mail apps.

  • How does MPP affect open tracking?

    Apple preloads images via proxy, causing nearly all emails to appear “opened,” regardless of actual engagement.

  • Can senders distinguish false opens from real ones?

    No — Apple’s proxy behavior makes all opens appear identical.

  • Does MPP affect click tracking?

    Early testing shows no impact: URLs, querystrings, and user agents remain untouched.

  • How does Private Relay affect IP-based data?

    It masks IPs and generalizes location, but still provides city-level or regional accuracy depending on user settings.

  • How many users rely on Apple Mail today?

    About 38% of all opens in the Benchmark Report come from Apple Mail clients.

  • Which email tactics break under MPP?

    Open-based segmentation, send-time optimization, open-time personalization, device-detection widgets, and countdown timers.

  • What should senders use instead of opens?

    Clicks, conversions, browsing behavior, purchase data, and deeper engagement signals that reflect real user intent.

If you’re an #emailgeek, you’ve no doubt heard the news from Apple this week on a big change that will have an impact on email when it comes to open tracking. We wanted to share what we know and our points of view as of now, but this information will evolve as we learn more. We’ll be sure to continue updating this post and sharing new content in the coming weeks and months as we learn more.

If you’re an #emailgeek, you’ve no doubt heard the news from Apple this week on a big change that will have an impact on email when it comes to open tracking. We wanted to share what we know and our points of view as of now, but this information will evolve as we learn more. We’ll be sure to continue updating this post and sharing new content in the coming weeks and months as we learn more.

If you’re an #emailgeek, you’ve no doubt heard the news from Apple this week on a big change that will have an impact on email when it comes to open tracking. We wanted to share what we know and our points of view as of now, but this information will evolve as we learn more. We’ll be sure to continue updating this post and sharing new content in the coming weeks and months as we learn more.

As an email sender, does this mean I won’t be able to track opens for Apple Mail users?

We do think that many users will opt-in to select the “Protect Mail Activity” option when it’s presented to them. We think that reporting will over inflate the number of opens given Apple appears to be loading the tracking pixels via relay or proxy for users that have opted into privacy. Testing on our end has confirmed that in some cases Apple is preloading images in an email, even for emails that have not been opened.* You won’t be able to discern these false opens from real ones.

We do think that many users will opt-in to select the “Protect Mail Activity” option when it’s presented to them. We think that reporting will over inflate the number of opens given Apple appears to be loading the tracking pixels via relay or proxy for users that have opted into privacy. Testing on our end has confirmed that in some cases Apple is preloading images in an email, even for emails that have not been opened.* You won’t be able to discern these false opens from real ones.

We do think that many users will opt-in to select the “Protect Mail Activity” option when it’s presented to them. We think that reporting will over inflate the number of opens given Apple appears to be loading the tracking pixels via relay or proxy for users that have opted into privacy. Testing on our end has confirmed that in some cases Apple is preloading images in an email, even for emails that have not been opened.* You won’t be able to discern these false opens from real ones.

What’s happening?

Apple announced Mail Privacy Protection for their Mail app on iOS 15, iPadOS 15, and macOS Monterey devices. According to Apple, “Mail Privacy Protection stops senders from using invisible pixels to collect information about the user. [It prevents] senders from knowing when they open an email, and masks their IP address so it can’t be linked to other online activity or used to determine their location.”

Apple announced Mail Privacy Protection for their Mail app on iOS 15, iPadOS 15, and macOS Monterey devices. According to Apple, “Mail Privacy Protection stops senders from using invisible pixels to collect information about the user. [It prevents] senders from knowing when they open an email, and masks their IP address so it can’t be linked to other online activity or used to determine their location.”

Apple announced Mail Privacy Protection for their Mail app on iOS 15, iPadOS 15, and macOS Monterey devices. According to Apple, “Mail Privacy Protection stops senders from using invisible pixels to collect information about the user. [It prevents] senders from knowing when they open an email, and masks their IP address so it can’t be linked to other online activity or used to determine their location.”

When is this happening?

While no date has been set, it is expected to launch as early as September, but possibly as late as November.

While no date has been set, it is expected to launch as early as September, but possibly as late as November.

While no date has been set, it is expected to launch as early as September, but possibly as late as November.

How will users control their Mail Privacy Protection via their iOS 15 Mail app?

The below is how the privacy protection feature will be presented to all iOS 15 users:

Mail Privacy Protection screen on a smartphone displaying option to protect mail activity by hiding IP addresses.

Image source: Ryan Jones on Twitter.

The below is how the privacy protection feature will be presented to all iOS 15 users:

Mail Privacy Protection screen on a smartphone displaying option to protect mail activity by hiding IP addresses.

Image source: Ryan Jones on Twitter.

The below is how the privacy protection feature will be presented to all iOS 15 users:

Mail Privacy Protection screen on a smartphone displaying option to protect mail activity by hiding IP addresses.

Image source: Ryan Jones on Twitter.

What are the resulting implications when “Protect Mail Activity” is selected by a user?

Testing on our end has confirmed that in some cases Apple is preloading images in an email, even for emails that have not been opened. This means almost all emails sent to recipients using the Mail App may have obfuscated results showing false opens.

Testing on our end has confirmed that in some cases Apple is preloading images in an email, even for emails that have not been opened. This means almost all emails sent to recipients using the Mail App may have obfuscated results showing false opens.

Testing on our end has confirmed that in some cases Apple is preloading images in an email, even for emails that have not been opened. This means almost all emails sent to recipients using the Mail App may have obfuscated results showing false opens.

Does it matter if the user is on Gmail or some other mail service?

The mail service doesn’t matter here. The endpoint of where the email is opened is what’s important here. If an email is opened on the Mail app on iOS 15, iPadOS 15, and macOS Monterey devices, it will have the option to not be tracked via the user privacy selection shown in the screenshot above.

The mail service doesn’t matter here. The endpoint of where the email is opened is what’s important here. If an email is opened on the Mail app on iOS 15, iPadOS 15, and macOS Monterey devices, it will have the option to not be tracked via the user privacy selection shown in the screenshot above.

The mail service doesn’t matter here. The endpoint of where the email is opened is what’s important here. If an email is opened on the Mail app on iOS 15, iPadOS 15, and macOS Monterey devices, it will have the option to not be tracked via the user privacy selection shown in the screenshot above.

What if the user has iOS 15 and is using the Gmail app?

It’s not the operating system alone allowing for this tracking. It’s only when the user has iOS 15 AND checks their mail via the native Apple Mail app. If the user is on Gmail or another mail app that is not Apple Mail, even if on iOS 15, the privacy controls will not be in effect.

It’s not the operating system alone allowing for this tracking. It’s only when the user has iOS 15 AND checks their mail via the native Apple Mail app. If the user is on Gmail or another mail app that is not Apple Mail, even if on iOS 15, the privacy controls will not be in effect.

It’s not the operating system alone allowing for this tracking. It’s only when the user has iOS 15 AND checks their mail via the native Apple Mail app. If the user is on Gmail or another mail app that is not Apple Mail, even if on iOS 15, the privacy controls will not be in effect.

How many people use Apple’s Mail App?

As the world’s largest email sender delivering 40% of the world’s commercial and transactional email, we have a fairly good view of the world’s email footprint. In our 2021 Benchmark Report, we saw 38.1% of all opens and clicks coming from one of the Apple Mail app clients, with 25.7% on iPhone, 9.6% on desktop and 2.8% on iPad. This is second only to Gmail (on mobile and desktop) as the largest market share of any device/client family.

As the world’s largest email sender delivering 40% of the world’s commercial and transactional email, we have a fairly good view of the world’s email footprint. In our 2021 Benchmark Report, we saw 38.1% of all opens and clicks coming from one of the Apple Mail app clients, with 25.7% on iPhone, 9.6% on desktop and 2.8% on iPad. This is second only to Gmail (on mobile and desktop) as the largest market share of any device/client family.

As the world’s largest email sender delivering 40% of the world’s commercial and transactional email, we have a fairly good view of the world’s email footprint. In our 2021 Benchmark Report, we saw 38.1% of all opens and clicks coming from one of the Apple Mail app clients, with 25.7% on iPhone, 9.6% on desktop and 2.8% on iPad. This is second only to Gmail (on mobile and desktop) as the largest market share of any device/client family.

Why is Apple doing this?

Apple has long held the belief that privacy is a fundamental human right. It matches what a lot of governments in industrial nations across the world have been leaning into. This is something they are able to do as the owner of the distribution channel, and it’s a trend we’ve seen Apple follow with capping the IDFA tracking on other apps on the App Store, which has come with a fight from Facebook. Apple initiated these types of changes in email last year when they launched the Private Email Relay service which allows users to sign into apps with an anonymous, unique email address. With the release of iOS 14.5, when US-based users were prompted to authorize tracking by an app, 96% of the time they opted out of tracking, so we believe adoption of this new privacy feature will be extremely broad.  We’ve also seen the demise of third-party cookies in the advertising industry, including on Apple’s Safari. It was inevitable that Apple would lean into privacy on open tracking too. 

Apple has long held the belief that privacy is a fundamental human right. It matches what a lot of governments in industrial nations across the world have been leaning into. This is something they are able to do as the owner of the distribution channel, and it’s a trend we’ve seen Apple follow with capping the IDFA tracking on other apps on the App Store, which has come with a fight from Facebook. Apple initiated these types of changes in email last year when they launched the Private Email Relay service which allows users to sign into apps with an anonymous, unique email address. With the release of iOS 14.5, when US-based users were prompted to authorize tracking by an app, 96% of the time they opted out of tracking, so we believe adoption of this new privacy feature will be extremely broad.  We’ve also seen the demise of third-party cookies in the advertising industry, including on Apple’s Safari. It was inevitable that Apple would lean into privacy on open tracking too. 

Apple has long held the belief that privacy is a fundamental human right. It matches what a lot of governments in industrial nations across the world have been leaning into. This is something they are able to do as the owner of the distribution channel, and it’s a trend we’ve seen Apple follow with capping the IDFA tracking on other apps on the App Store, which has come with a fight from Facebook. Apple initiated these types of changes in email last year when they launched the Private Email Relay service which allows users to sign into apps with an anonymous, unique email address. With the release of iOS 14.5, when US-based users were prompted to authorize tracking by an app, 96% of the time they opted out of tracking, so we believe adoption of this new privacy feature will be extremely broad.  We’ve also seen the demise of third-party cookies in the advertising industry, including on Apple’s Safari. It was inevitable that Apple would lean into privacy on open tracking too. 

How much will this impact email senders?

Opens are not a perfect metric, and it has always come with flaws. It does, however, tell you engagement trends over time. Some call it a vanity metric, which is a myopic view. The technology behind opens powers more than an engagement metric (even if that metric is flawed). It also makes a lot of the cool innovation in the email space possible, which is now up to question. 

There’s a lot to unpack here, but here is what we think the impact will be:

  • Lack of being able to use opens as part of a list hygiene/segmentation strategy. Without access to opens, senders will need to rely on clicks and deeper behaviors to know if a real human is still there and interested in the content to keep receiving it. Opens (and the lack-thereof) have long been an important leading indicator of user disengagement which promoted early removal/retargeting of disengaged users. Some senders might even fall into bad sending practices by not having this metric to use for segmentation. We suspect Q4 (and beyond) deliverability might be challenging for some senders that aren’t ready for this.

  • Subject line testing that relies upon open tracking will be flawed. This will no longer be an easy thing to test for Apple Mail users. Metrics like clicks and conversions that are further down the email conversion funnel from the subject line will have to be used. Companies that use Natural Language Processing to optimize subject lines will need to rethink their strategy in order to update the algorithms that support the effectiveness of their products when it comes to recipients using the Mail App. However, subject line testing that relies upon data from panel engagement, such as SparkPost subject line predict and subject line advisor, will continue to provide relevant insights and predictions.

  • Send-time optimization will also be flawed because it often takes opens into account as part of its algorithm to determine the right time to send the email based on open and click engagement. We do believe that products like Verizon’s View Time Optimization will be unaffected by this.

  • Open-time personalization/live content will be broken. We’ve seen cool innovation in recent years with weather widgets and store locators based on your location at the time of open. Other innovations that will be impacted will be device trackers that detect the operating system to tell you to download the app via the App Store or Google Play. Countdown timers will probably not work due to the caching by Apple at mail inception. Anything that draws from context at the time of open (location, time, device, etc) through open tracking is potentially at risk.

  • Data strategies for locale-specific privacy laws (like GDPR) or service availability will need to be rethought if they use email opens or clicks from emails to establish recipient residency.

  • Monitoring inbox placement will become an even more crucial metric to track because assuming your emails have landed in the inbox based on opens will no longer be reliable.

Opens are not a perfect metric, and it has always come with flaws. It does, however, tell you engagement trends over time. Some call it a vanity metric, which is a myopic view. The technology behind opens powers more than an engagement metric (even if that metric is flawed). It also makes a lot of the cool innovation in the email space possible, which is now up to question. 

There’s a lot to unpack here, but here is what we think the impact will be:

  • Lack of being able to use opens as part of a list hygiene/segmentation strategy. Without access to opens, senders will need to rely on clicks and deeper behaviors to know if a real human is still there and interested in the content to keep receiving it. Opens (and the lack-thereof) have long been an important leading indicator of user disengagement which promoted early removal/retargeting of disengaged users. Some senders might even fall into bad sending practices by not having this metric to use for segmentation. We suspect Q4 (and beyond) deliverability might be challenging for some senders that aren’t ready for this.

  • Subject line testing that relies upon open tracking will be flawed. This will no longer be an easy thing to test for Apple Mail users. Metrics like clicks and conversions that are further down the email conversion funnel from the subject line will have to be used. Companies that use Natural Language Processing to optimize subject lines will need to rethink their strategy in order to update the algorithms that support the effectiveness of their products when it comes to recipients using the Mail App. However, subject line testing that relies upon data from panel engagement, such as SparkPost subject line predict and subject line advisor, will continue to provide relevant insights and predictions.

  • Send-time optimization will also be flawed because it often takes opens into account as part of its algorithm to determine the right time to send the email based on open and click engagement. We do believe that products like Verizon’s View Time Optimization will be unaffected by this.

  • Open-time personalization/live content will be broken. We’ve seen cool innovation in recent years with weather widgets and store locators based on your location at the time of open. Other innovations that will be impacted will be device trackers that detect the operating system to tell you to download the app via the App Store or Google Play. Countdown timers will probably not work due to the caching by Apple at mail inception. Anything that draws from context at the time of open (location, time, device, etc) through open tracking is potentially at risk.

  • Data strategies for locale-specific privacy laws (like GDPR) or service availability will need to be rethought if they use email opens or clicks from emails to establish recipient residency.

  • Monitoring inbox placement will become an even more crucial metric to track because assuming your emails have landed in the inbox based on opens will no longer be reliable.

Opens are not a perfect metric, and it has always come with flaws. It does, however, tell you engagement trends over time. Some call it a vanity metric, which is a myopic view. The technology behind opens powers more than an engagement metric (even if that metric is flawed). It also makes a lot of the cool innovation in the email space possible, which is now up to question. 

There’s a lot to unpack here, but here is what we think the impact will be:

  • Lack of being able to use opens as part of a list hygiene/segmentation strategy. Without access to opens, senders will need to rely on clicks and deeper behaviors to know if a real human is still there and interested in the content to keep receiving it. Opens (and the lack-thereof) have long been an important leading indicator of user disengagement which promoted early removal/retargeting of disengaged users. Some senders might even fall into bad sending practices by not having this metric to use for segmentation. We suspect Q4 (and beyond) deliverability might be challenging for some senders that aren’t ready for this.

  • Subject line testing that relies upon open tracking will be flawed. This will no longer be an easy thing to test for Apple Mail users. Metrics like clicks and conversions that are further down the email conversion funnel from the subject line will have to be used. Companies that use Natural Language Processing to optimize subject lines will need to rethink their strategy in order to update the algorithms that support the effectiveness of their products when it comes to recipients using the Mail App. However, subject line testing that relies upon data from panel engagement, such as SparkPost subject line predict and subject line advisor, will continue to provide relevant insights and predictions.

  • Send-time optimization will also be flawed because it often takes opens into account as part of its algorithm to determine the right time to send the email based on open and click engagement. We do believe that products like Verizon’s View Time Optimization will be unaffected by this.

  • Open-time personalization/live content will be broken. We’ve seen cool innovation in recent years with weather widgets and store locators based on your location at the time of open. Other innovations that will be impacted will be device trackers that detect the operating system to tell you to download the app via the App Store or Google Play. Countdown timers will probably not work due to the caching by Apple at mail inception. Anything that draws from context at the time of open (location, time, device, etc) through open tracking is potentially at risk.

  • Data strategies for locale-specific privacy laws (like GDPR) or service availability will need to be rethought if they use email opens or clicks from emails to establish recipient residency.

  • Monitoring inbox placement will become an even more crucial metric to track because assuming your emails have landed in the inbox based on opens will no longer be reliable.

How will it affect the products I use at Bird?

We’re ready for this big industry change in our products. You can read more about it in our detailed article on the industry change.

These are our initial thoughts on what this means for the email community. We’ll continue to give updates and share content on how you can be ready for this change that will be here before we know it.

We’re ready for this big industry change in our products. You can read more about it in our detailed article on the industry change.

These are our initial thoughts on what this means for the email community. We’ll continue to give updates and share content on how you can be ready for this change that will be here before we know it.

We’re ready for this big industry change in our products. You can read more about it in our detailed article on the industry change.

These are our initial thoughts on what this means for the email community. We’ll continue to give updates and share content on how you can be ready for this change that will be here before we know it.

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A person is standing at a desk while typing on a laptop.

The complete AI-native platform that scales with your business.

Contact sales

Start for free

© 2025 Bird

Contact Support

A person is standing at a desk while typing on a laptop.

The complete AI-native platform that scales with your business.

Contact sales

Start for free

© 2025 Bird

Contact Support