When comparing Postbox vs Boxy, the Slant community recommends Postbox for most people. In the question“What are the best e-mail clients for macOS?” Postbox is ranked 7th while Boxy is ranked 22nd.
Ranked in these QuestionsQuestion Ranking
Pro Clear interface
Pro Forgotten attachment reminders by default
Reminding the user that they forgot to attach the file if they mentioned one in the body of the email is one of the most useful features of any email client and so many don't include this. Postbox is pre-configured to look for certain keywords (attached, CV, spreadsheet, pdf etc) and you can specify your own keywords in addition.
Pro Blocks tracking gifs
Has the ability to block tracking gifs commonly used for read receipts.
Pro One Inbox for all accounts
All messages in one place. But you can select to show only messages from each account either.
Pro Quick Bar for macros
Quick bar allows you to add a variety of content to your message. It will let you reuse URLS in your Sent folder, and autocompletes against canned responses, signatures, and topics.
Pro Native Google Inbox for Mac
Boxy is simply a wrapper around Google Inbox. People who are used to Inbox's web interface will feel right at home with Boxy.
Pro Surfaces important information from messages
If an email contains pictures, flight information, reservation at a restaurant, attachments, links, dates, phone numbers and other information that the application recognizes, it will surface that information in its main view. These items can be viewed and interacted with without having to open the message itself. It allows finding and taking action on the important email information quickly.
Pro Intelligent categorization
Inbox tries automatically bundling similar messages together. For example, Inbox will create bundles for travel information, receipts, promotions as well as group messages temporally. It enables also managing these bundles of messages together - they can all be swiped away together.
Con No support forum
Support for paid product has no online forums.
Con Only supports Gmail accounts
No exchange email support or importing of any other e-mail services mail.