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Microsoft Outlook for iOS and Android vs FairEmail: catalog facts
Microsoft Outlook for iOS and Android	FairEmail
Freemium The app is a free download; Microsoft 365 plans are sold separately.	Free Free to download from Google Play, F-Droid or GitHub releases.
Android, iOS	Android
Email, calendar and contacts in one app Available on both iOS and Android phones and tablets	Works with nearly all IMAP providers and unlimited accounts OpenPGP and S/MIME encryption built in
Closed source Closely tied to Microsoft's services and plans	No Microsoft Exchange Web Services or ActiveSync support Android only
Downloadable app	Downloadable app
Closed source	Open source
License not stated	License: GPL-3.0
Not stated if an account is needed	Not stated if an account is needed
Not stated if it works offline	Works offline
Official website Full listing and sources Checked September 23, 2026	Official website Full listing and sources Checked September 23, 2026

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