What is the best way to estimate US consumer email inbox market share between Gmail and Apple Mail?
Summary
What email marketers say11Marketer opinions
Email marketer from Validity, previously ReturnPath, shares that filtering practices and algorithms can greatly affect open rates in both Gmail and Apple Mail, thus impacting the reliability of open-rate metrics for market share estimation.
Email marketer from Email Marketing Help explains that many published statistics are inaccurate due to changes in how email clients handle image loading and privacy features like MPP. Real-world testing is recommended.
Email marketer from MessageBird, formerly SparkPost, explains deliverability can vary significantly between Gmail and Apple Mail due to differing spam filters and authentication protocols. Monitoring deliverability metrics can offer indirect insights.
Email marketer from Email Geeks believes Litmus is the closest for inbox market share. Anecdotally, many read Gmail emails through Apple clients.
Email marketer from Litmus explains that email client market share fluctuates, but Apple iPhone and Gmail typically hold significant positions. It's important to track trends over time for accurate estimates.
Email marketer from EmailToolTester shares that estimating market share depends on the methodology used (e.g., open rates, user agent analysis) and can be influenced by factors like mobile vs. desktop usage.
Email marketer from Email Geeks shares that with various caches and proxies obfuscating user agents, any attempt to reliably track MUA market share using images will fail, adding that many stats are mostly wrong.
Email marketer from Email Geeks questions if the inquiry pertains to the application being used or the mailbox provider. He then shares the emails can be in a “Google Inbox” but the user will read it in “Apple Mail,” Gmail’s webmail, or the Yahoo Mail app.
Email marketer from Mailjet suggests running A/B tests with tailored content for Gmail and Apple Mail users (if identifiable) to measure engagement differences and potentially infer market share differences within your audience.
Email marketer from Statista shares that in October 2023, Apple Mail accounted for 58.7 percent of the email client market share in the United States, with Gmail accounting for 28.9 percent.
Email marketer from Reddit suggests focusing on list segmentation and tracking engagement within your own lists to gauge the relative usage of Gmail and Apple Mail among your specific audience.
What the experts say1Expert opinion
Expert from Word to the Wise explains that Apple's Mail Privacy Protection (MPP) significantly distorts open rate metrics, rendering them unreliable for estimating market share. Focus should shift towards click rates and other engagement metrics.
What the documentation says5Technical articles
Documentation from Apple explains that Mail Privacy Protection (MPP) in Apple Mail impacts open rate tracking. MPP makes estimating market share based on opens unreliable due to inflated open rates.
Documentation from Mozilla explains the challenges in accurately identifying Mail User Agents (MUAs) due to the diversity of clients and the obfuscation techniques they employ.
Documentation from Google shares that Gmail supports AMP for Email, enabling interactive experiences. Tracking AMP usage can provide some insight into Gmail's user engagement with advanced email features.
Documentation from Yahoo shares that robust authentication practices (SPF, DKIM, DMARC) can improve deliverability, indirectly aiding in more accurate open rate tracking where MPP is not in effect, which helps estimate user engagement in certain segments.
Documentation from IETF shares that parsing user agent strings is one method, although unreliable, of identifying email clients. Standards define user agent string formats, but they can be easily spoofed.