Astro by Slack is described as 'Modern email and calendar apps for Mac, iOS, Android, Slack and Alexa, powered by Artificial Intelligence. Astro keeps you focused on what's most important' and is a Email Client in the office & productivity category. There are more than 25 alternatives to Astro by Slack for a variety of platforms, including Windows, Mac, Android, iPhone and iPad apps. The best Astro by Slack alternative is Thunderbird, which is both free and Open Source. Other great apps like Astro by Slack are K-9 Mail, Microsoft Outlook, FairEmail and Spark Mail.
Streamline your email experience by managing multiple accounts, integrating apps like Slack and Google Calendar, and using AI-driven features like drafting and spam prevention. Customize your workspace with themes, notifications, and tools for improved productivity and a modern interface.
United States
Cross-platform email client supporting multiple identities, chat, and strong filtering. Extend functionality with add-ons like RSS/Atom feed readers and PGP support.
United States
K-9 is an open source email client for Android with multi-folder sync, email signatures, Bcc-to-self, return-address configuration, keyboard shortcuts, Exchange Support, message flagging, IMAP deletes, saving attachments, configurable notifications and more.
Streamline emails, calendars, contacts, and task management with a smart inbox prioritizing critical messages. Includes calendar scheduling, third-party app integration like Facebook, Dropbox, and Trello, and support for Microsoft Exchange, Outlook.com, and Gmail, ensuring efficient task and email handling.
United States
Open-source, privacy-focused email client offering features such as encryption via OpenPGP and S/MIME, unlimited accounts, a unified inbox, customizable settings, and reformatted emails to prevent phishing. Supports two-way synchronization and provides Pro features for additional customization.
Netherlands
EU
E-mail app with all the great features: swipes (long/short), snooze, add (multiple) attachments from the cloud, support for various e-mail services and more.
Ukraine
Zoho Mail is a secure, encrypted, and enterprise-ready email solution, a suite of apps tailor-made for your organization's needs.
India
Boost your productivity and send better email with Mailspring, a beautiful, fast email client for Mac, Windows, and Linux. Mailspring is free to use and an optional pro version adds read receipts, send later, reminders and more.
United States
eM Client is a full featured e-mail client with a modern and easy to use interface. eM Client also offers calendar, tasks, contacts, notes and chat.
CzechiaEU
Access, view and manage messages from all your email accounts in one place. Categorize your messages into easy to browse categories. Catch up on email easily with Apple Intelligence powered Priority Messages and summarizations.
United States
Email and news client on GTK+ foundation featuring quick performance, extensible plugins, secure protocols, advanced filtering, strong folder and contact management, lightweight design, powerful search, customizable interface, multi-language support, and encryption.
Secure email app for Mac, iPhone, Android and Windows with AI Copilot, PGP encryption, read receipts and one unified inbox.
Singapore
BlueMail is a modern, mobile first, powerful Email management tool with a sleek design, unified inbox and support for all your accounts: IMAP,Exchange,POP3.
United States
