5 Email Design Best Practices Every Marketer Should Know

https://blog.aweber.com/email-marketing/the-5-email-design-best-practices-every-marketer-should-know.htm

For Devs: A Fix for Gmail’s iOS App Font Size Increase

http://freshinbox.com/blog/gmail-on-ios-increases-font-size-on-some-emails/

Email newsletter truncation in iOS Mail

https://www.campaignmonitor.com/blog/post/3857/ios-email-truncation