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Microsoft Outlook for iOS and Android vs Spark Mail: catalog facts
Microsoft Outlook for iOS and Android	Spark Mail
Freemium The app is a free download; Microsoft 365 plans are sold separately.	Freemium Free for individuals; paid plans add AI features and team tools.
Android, iOS	Windows, macOS, Android, iOS
Email, calendar and contacts in one app Available on both iOS and Android phones and tablets	Automatic inbox categorization cuts down on manual sorting AI-drafted replies can speed up routine email responses
Closed source Closely tied to Microsoft's services and plans	AI and team features are gated behind a paid plan Some categorization requires manual correction over time
Downloadable app	Downloadable app
Closed source	Closed source
License not stated	License not stated
Not stated if an account is needed	Not stated if an account is needed
Not stated if it works offline	Not stated if it works offline
Official website Full listing and sources Checked September 23, 2026	Official website Full listing and sources Checked September 22, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.