Polymail - Native email app for email productivity.
Microsoft Outlook - Organize your world. Outlook’s email and calendar tools help you communicate, stay on top of what matters, and get things done.
Canary Mail - Privacy-aware email app for Mac & iOS
Gmail - Gmail is available across all your devices Android, iOS, and desktop devices. Sort, collaborate or call a friend without leaving your inbox.
Flow-e - Turn your Gmail or Office365 inbox to a Visual Task Board.
Zoho Mail - Zoho Mail is a secure, encrypted, and enterprise-ready email solution, a suite of apps tailor-made for your organization's needs.