A New (Free) Tool for Mobile Optimization

Mobile has won, and this changes the game. When I speak to email marketers on product discovery calls, they talk about their desire to advance their companies by prioritizing mobile, but often feel their hands are tied. If you’re an email marketer, you probably don’t have free reign to follow every best practice that helps you stand out in the inbox and optimizes your mobile marketing. And you also know there’s less time to capture customer attention than ever before. In fact, research suggests you only have 3 seconds to entice iPhone readers.

Geo Email Monitor is a free tool Return Path recently released for marketers to optimize their email programs, specifically for mobile. Marketers use this free tool to experiment and determine which changes to their email program will drive more customer activity, specifically mobile activity.

There are plenty of best practices for email marketing on mobile. It’s generally recommended that if you want to increase mobile opens, you should shorten subject lines or personalize send times so your message arrives at the optimal time in each time zone. Recommendations have good intentions, but they may not have an impact on your specific goals or be possible with your email sending platform. Rather than following every best practice for mobile optimization out there, try testing strategies and move forward with the version that drives more mobile opens and reads. This will allow you to find what boosts mobile readership, specifically for your customers.

Smart marketers test and measure success with the right metrics
Smart marketers test. They tweak one element at a time, testing their subject line, preheader, design, and more. The winning version survives. When setting up these A/B tests, the successful criterion is usually always unique opens. But unique opens aren’t always the best measure of success, especially if your goal is optimizing for mobile. If you’re trying to increase mobile readership by testing different subject line lengths, then shouldn’t your winner be the version with more mobile opens, not the one with the best open or click rate? With Geo Email Monitor, marketers can measure if a change actually drives more mobile opens. They also can also measure success by desktop opens, webmail opens, and even opens in specific US geographic regions.

Test for mobile optimization using Geo Email Monitor
To use Geo Email Monitor for your own testing, you’ll create two different campaign tracking codes for an A and B version of a campaign (you get 6 free each month, by the way). Add the A version of the tracking code to one email, the B version to the other, and then send. You can vary subject line length, pre-header text, send time/day, or even alter your “from” address. But try not to alter more than one element at a time. Geo Email Monitor reports your results as soon as customers open your emails, so you can determine which version resonated with your mobile opening customers.

A test to try today
Once you know which platform your customers usually use to read your email, try testing subject line length variations. If you don’t know if your customers read more on mobile or desktop or webmail, first send an email to your list with a Geo Email Monitor tracking code embedded to see if you have more mobile or desktop readers.

  • If your customers primarily use mobile, try this A/B test. Version A has an average length subject line (41-50 characters) and Version B has a shorter length subject line (21-40 characters).
  • If your customers primarily use desktop or webmail, try this A/B test. Version A has an average length subject line (41-50 characters). Version B has longer than average subject line (61-70 characters).

Other than the length, keep the contents and theme of the subject line consistent so you can see which test performed the best.


Next step, optimize for mobile reads
Optimizing for mobile opens is a stepping stone to a mobile oriented email program. Some Return Path customers are diving even deeper into optimizing not just for mobile opens, but for mobile reads. Once a subscriber has opened your email on a mobile device, Email Client Monitor, a Return Path tool, reports on whether subscribers are truly engaging with your message (reading for over eight seconds), skimming it (reading for two to seven seconds) or simply abandoning it (leaving before two seconds). Being able to measure the duration subscribers spend on a message unlocks opportunities for marketers to test the contents of a message using a success metric that is more closely tied to customer engagement than clicks. Marketers are using Email Client Monitor to run A/B tests that measure whether changes, such as a different hero image, actually improve mobile reader engagement.


If you learn something interesting in your own mobile optimization testing, please share what you find works for your own mobile customers in the comments below.

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