Spark Mail
Unified inbox from Readdle with message and inbox side by side when unfolded
Readdle Technologies Limited · Productivity · Free · in-app purchases
iPhone screenshots
iPad screenshots
How it uses iPhone Duo
Readdle's release notes for Spark 3.20.1 say the app is ready for iPhone Duo from launch day. On the unfolded display, the inbox and the open message can appear side by side. Readdle says the same actions and content are available whether the phone is closed, open or partially folded, and that unfolding gives more space for reading, writing, search and the calendar. We have not yet tested it on an iPhone Duo.
What’s New
Version 3.20.3 ·
Spark is ready for iPhone Duo from day one! See your inbox and the open message side by side. Closed, open, or partially folded, you get the same actions and content. Unfold your iPhone Duo to get more room for reading, writing, search, and calendar. Update now and let us know what you think!
About this app
Spark Mail is an email client from Readdle that brings Gmail, Outlook, iCloud, Yahoo, AOL and any IMAP account into one unified inbox. Its Smart Inbox puts messages from people ahead of newsletters and notifications, which are grouped below. Everyday tools include marking emails as done, setting them aside for later, muting threads, scheduled sending that works even when the device is off, and Smart Search with Smart Folders. Gatekeeper lets users screen first-time senders, and priority senders can be pinned to the top. Spark +AI can summarize long threads, draft and rephrase replies, adjust tone and translate messages. The app also connects calendars, links to tools such as Notion, Asana and Things, and offers team features including shared drafts, private comments, message assignment and shareable links to individual emails. Spark is free to download, with paid plans for its premium and team features. Version 3.20.1, released on October 22, 2026, is Readdle's iPhone Duo update. The developer says the inbox and an open message can be shown side by side, the same actions are available whether the phone is closed, open or partly folded, and unfolding gives more room for reading, writing, search and calendar.
App Store descriptionWritten by the developer.
Manage priorities, not emails. Spark brings every account into one inbox and automatically surfaces what matters most — so nothing slips through the cracks. Loved by millions and named "Best of the App Store" by Apple. "It's a combination of polish, simplicity, and depth." — FastCompany "You can create an email experience that works for you." — TechCrunch EVERY ACCOUNT, EVERY EMAIL, IN ONE PLACE Connect Gmail, Outlook, iCloud, Yahoo, AOL, Hotmail, GMX, and any IMAP account in a single unified inbox. STAY ORGANIZED WITH SMART INBOX Important emails from real people rise to the top. Newsletters and notifications stay neatly grouped below, out of your way. GET MORE DONE WITH EMAIL ESSENTIALS Mark emails as done or set them aside for later Mute threads you're no longer following Schedule emails to send later — even if your device is off Find anything fast with Smart Search and Smart Folders PROTECT YOUR INBOX WITH GATEKEEPER Pre-screen new senders and block unwanted contacts instantly. PRIORITIZE WHAT MATTERS Mark important senders so their emails always stay on top. Group emails by sender or domain to keep your inbox clean. WRITE FASTER WITH SPARK +AI Summarize long threads, draft replies, rephrase messages, and adjust tone. Your AI Assistant helps you clear your inbox, translate emails, and keep projects moving. MANAGE YOUR CALENDAR AND MEETINGS Connect your calendars to stay on top of your day in one app. CONNECT YOUR FAVORITE TOOLS Link Spark to Notion, Asana, Things, and 10+ integrations to act on everything in your inbox. COLLABORATE WITH YOUR TEAM Co-author emails and discuss in private comments Assign messages so everyone knows who owns what Share secure links to specific emails Track read receipts to keep work moving SECURE AND PRIVATE Spark encrypts your data, runs on Google Cloud's secure infrastructure, and is fully GDPR compliant. TRY IT FREE Stick with our powerful free plan, or try Spark Plus or Spark Pro free for 7 days. Download Spark and reclaim your day. FAQ Is Spark the best email app for managing multiple accounts? Spark brings Gmail, Outlook, iCloud, Yahoo, and any IMAP account into one unified inbox, so you can manage every email in one place instead of switching between apps. How is Spark different from Apple Mail and Gmail? Spark helps you focus on what matters, not just read email. It automatically prioritizes messages from real people, keeps newsletters out of the way, and can summarize, draft, and follow up so less falls through the cracks. How does Spark help with email overload? Spark surfaces important messages first, lets you snooze emails until you're ready, and helps you reach Inbox Zero without the grind. Higher plans flag what needs attention so nothing gets missed. Does Spark have AI features? Yes. Spark uses AI to write faster, reply clearly, and summarize threads. On Plus, AI helps you make better inbox decisions. On Pro, it acts on your behalf — drafting, organizing, and following up. Is Spark good for team collaboration? Yes. Teams can share drafts, comment privately, assign messages, and manage shared inboxes — no forwarding chains. Collaboration is available on Pro. Can I schedule emails to send later? Yes. Schedule any email to send at the right time, or snooze incoming messages to return when you're ready. Is Spark free? Yes. Spark is free to download and use. Spark Plus is for professionals who want a more focused inbox; Spark Pro is for those who need Spark to handle follow-through so nothing gets missed. Is Spark available on Mac, iPhone, and iPad? Yes. Spark works on iOS, iPadOS and macOS, and stays in sync across all your devices. Spark is made by Readdle. Terms of Service: https://sparkmailapp.com/legal/terms Privacy Policy: https://sparkmailapp.com/legal/privacy-app Help: support@sparkmailapp.com
Highlights
- Unified inbox for Gmail, Outlook, iCloud and IMAP accounts
- Smart Inbox grouping newsletters and notifications
- Gatekeeper for screening new senders
- Scheduled send, snooze and mute
- Spark +AI summaries, drafting and translation
- Built-in calendar
- Inbox and message side by side on unfolded iPhone Duo
Spark Mail on iPhone Duo: FAQ
Is Spark Mail optimized for iPhone Duo?
Yes. Spark Mail is Built for Duo: it uses the fold, Split View or the outer display. Verified on October 22, 2026 (Developer statement).
What does Spark Mail look like on iPhone Duo?
Readdle's release notes for Spark 3.20.1 say the app is ready for iPhone Duo from launch day. On the unfolded display, the inbox and the open message can appear side by side. Readdle says the same actions and content are available whether the phone is closed, open or partially folded, and that unfolding gives more space for reading, writing, search and the calendar. We have not yet tested it on an iPhone Duo.
How much does Spark Mail cost?
Spark Mail costs Free · in-app purchases on the App Store.
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