Spark Mail - Spark helps you take your inbox under control. Instantly see what’s important and quickly clean up the rest. Spark for Teams allows you to create, discuss, and share email with your colleagues
Express Mail - Best mobile email app for Salespeople
Mastermind Manager - Software for running mastermind groups
myMail - myMail is the smart email app for managing all your accounts on iOS and Android.
Microsoft Outlook - Organize your world. Outlook’s email and calendar tools help you communicate, stay on top of what matters, and get things done.
K-9 Mail - K-9 is an opensource email client making it easy to chew through large volumes of email.