eM Client vs Mailspring

eM Client is a desktop email application for Windows and macOS (with companion Android/iOS apps) positioned as an alternative to Outlook and Thunderbird. It bundles email, calendar, tasks, notes, and chat into one interface, with inbox categorization, quick actions, and an AI add-on for drafting and summarizing. The free tier covers up to two accounts for personal, non-commercial use, while paid Personal and Business licenses remove that account limit and unlock features like PGP message encryption, snooze, translation, and mass mail tools. Licenses are available as annual subscriptions or one-time lifetime purchases, and mobile apps are free without a separate license.

Mailspring is a native desktop email client from independent studio Foundry376, built for Mac, Windows, and Linux. It unifies accounts from Gmail, iCloud, Office 365, Outlook.com, Yahoo, FastMail, and generic IMAP/SMTP providers into one fast, searchable inbox with Gmail-style search syntax. Its free tier covers core mail management, while the $8/month Pro plan adds read receipts, link tracking, send-later scheduling, follow-up reminders, templates, and contact enrichment (with limited weekly trials of Pro features in the free app). The client emphasizes native platform integration, including Windows taskbar badges, macOS notifications, and Linux system tray support.

• Flexible licensing: choose annual subscription or one-time lifetime purchase.
• Combines mail, calendar, tasks, and chat in one app instead of separate tools.
• Free tier is usable indefinitely for light personal use, not just a time-limited trial.
• Mature Outlook-style interface familiar to long-time Windows email users.

• Fast, native desktop performance rather than an Electron-wrapped web view for core mail actions.
• One of the few modern mail clients with first-class Linux support.
• Pro pricing is a simple flat $8/month rather than per-feature add-ons.
• Free tier lets users try Pro features on a limited weekly trial basis.

• Free tier is capped at 2 accounts, pushing regular multi-account users to a paid license.
• No native Linux desktop client, unlike some open-source competitors.
• Business per-device pricing can add up quickly for larger teams compared to per-user SaaS tools.

• Read receipts and link tracking require the recipient's email client to load remote content, which not all do.
• Development pace has slowed compared to some newer AI-native email clients.
• No official mobile app, so Mailspring is desktop-only.