Here are coding HTML email tips and tricks for work with Apple Mail, Outlook and Gmail email clients.
iPad and iPhone
Tips for coding email for iPad and iPhone devices, including iPad, iPhone, iPhone 5S, iPhone 6, iPhone 6+, iPhone 7 and iPhone 7+.
Gmail and Google Apps
Coding tips and workarounds for the Gmail and Google Apps webmail.
Office 365
Coding tips and workarounds for Office 365 webmail.
Yahoo!
Tips for coding emails for Yahoo! Mail.
Outlook.com
Coding tips for the numerous problems in Outlook.com webmail.
iOS
Coding tips for the numerous iOS email clients, including iOS, iOS X, iOS 5S, iOS 7, iOs 7+, iOS 8, and iOS 8+.
Gmail App
Tips for coding email for Gmail App 6 and 6+.
Thunderbird
How to tackle issues and coding pitfalls while using Thunderbird.
Windows Mail
Tips for coding emails for Yahoo! Mail.
Outlook
Coding tips for the numerous problems in the Outlook desktop application. Includes workarounds for Outlook 2003-2016.
Android
Coding tips for Android’s mobile email platforms, including Android 4.4.4 and Android 5, as well as Android’s Gmail/Gmail 5X, Outlook and Yahoo apps.