This document discusses optimizing emails for mobile devices like the iPhone. It found that emails optimized for mobile had higher open rates than regular emails. Specifically, an iPhone-optimized email template that was 400 pixels wide with a single column layout and large text/buttons had a 43.4% open rate, compared to a 39.8% open rate for the regular 750 pixel template. However, conversion rates did not increase, likely because the company's website was not mobile optimized. The document explores different optimization options and concludes it is still important to optimize emails for mobile even without increased conversions.