Thunderbird - Thunderbird is a free email application that's easy to set up and customize - and it's loaded with great features!
Webgility - Accounting, Bookkeeping and Inventory Automation for Retailers & Brands
Microsoft Outlook - Organize your world. Outlook’s email and calendar tools help you communicate, stay on top of what matters, and get things done.
Multiorders - Shipping and Inventory Management Software is easy way to save time.
eM Client - eM Client is a fully-featured email client for Windows and macOS with a clean and easy-to-use interface. eM Client also offers features for calendars, tasks, contacts, notes, and chat.
ChannelGrabber - ChannelGrabber is omnichannel eCommerce software for product content optimization, listings, inventory, order, shipping, invoice and message management. Integrates with eBay, Amazon, Shopify, and more.