Jun 9, 2021

Impact of iOS 15 Update On Open Tracking

Impact of iOS 15 Update On Open Tracking

Impact of iOS 15 Update On Open Tracking

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.

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.”

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.

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:

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.

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.

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.

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.

What about clicks? Will tracking on those be affected?

In our testing, we’ve determined that when “iCloud Private Relay” (which will be a part of the new iCloud+ offering) is enabled all web browsing activities through Safari are encrypted and routed through multiple proxy servers.  One interesting point to note is that Private Relay (at, least on our test device) worked just as well over HTTP or HTTPS.  This behavior is different than some sites are reporting, but in multiple tests our actual IP address was masked over both HTTP and HTTPS sites.

Additionally, early testing indicates that Apple will not modify the querystring nor are they changing the user agent string. So, first-party click tracking will likely not be impacted by this feature.  

When configuring Private Relay, the user is presented with two options for protecting their location information. The user can choose to have an anonymous IP address that preserves the user’s approximate location or they can choose to have an IP address that will be located in a broader region.  In our testing, the IP address when choosing the first option was located in the metropolitan area that the test lived within, but not identifiable to their home neighborhood.  When choosing the broader region option, the IP address was in an entirely different state, but still in the same country.  Assuming this behavior remains the same in the future, sites will still be able to use the IP information to make privacy compliance, segmentations, and similar geographic/regional decisions. 

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.

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. 

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.

How will it affect the products I use at SparkPost?

We’re ready for this big industry change in our products. You can read more about it here.

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.