Editing Microsoft Outlook (section)

==== Security ====
{{Update section|date=October 2022|reason=Data is secured with TLS version 1.2 over HTTPS connections end-to-end, between Microsoft 365 or Office 365 and the app, as per https://learn.microsoft.com/en-us/exchange/clients-and-mobile-in-exchange-online/outlook-for-ios-and-android/outlook-for-ios-and-android
|inaccurate=yes}}
Outlook mobile temporarily stores and indexes user data (including email, attachments, calendar information, and contacts), along with login credentials,<ref name=oauth-office-365>{{cite web|title=New access and security controls for Outlook for iOS and Android|url=https://blogs.office.com/2015/06/10/new-access-and-security-controls-for-outlook-for-ios-and-android|website=Office Blogs|date=June 10, 2015|access-date=June 10, 2015|archive-date=July 20, 2020|archive-url=https://web.archive.org/web/20200720105033/https://www.microsoft.com/de-de/microsoft-365/blog/2015/06/10/new-access-and-security-controls-for-outlook-for-ios-and-android/|url-status=dead}}</ref> in a "secure" form on [[Microsoft Azure]] servers located in the United States.<ref name=outlook_ios>{{cite web|title=Outlook for iOS and Android|url=https://technet.microsoft.com/EN-US/library/mt465744(v=exchg.150)|website=Microsoft TechNet|access-date=January 11, 2016|archive-date=April 13, 2020|archive-url=https://web.archive.org/web/20200413014426/https://docs.microsoft.com/en-us/exchange/clients/outlook-for-ios-and-android/use-basic-auth?view=exchserver-2019|url-status=live}}</ref> On Exchange accounts, these servers identify as a single [[Exchange ActiveSync]] user in order to fetch e-mail. Additionally, the app does not support [[mobile device management]], nor allows administrators to control how third-party [[cloud storage service]]s are used with the app to interact with their users. Concerns surrounding these security issues have prompted some firms, including the [[European Parliament]], to block the app on their Exchange servers.<ref name=networkworld-outlookapp>{{cite web|title=Outlook for iOS, Android flagged for inherent security flaws|url=https://www.networkworld.com/article/935186/outlook-for-ios-android-flagged-for-inherent-security-flaws.html|website=NetworkWorld|date=February 2, 2015|access-date=February 7, 2015|archive-date=April 28, 2024|archive-url=https://web.archive.org/web/20240428135719/https://www.networkworld.com/article/935186/outlook-for-ios-android-flagged-for-inherent-security-flaws.html|url-status=live}}</ref><ref name=techtarget-outlooksecurity>{{cite web|title=Security issues lead IT to block Outlook for iOS|url=http://searchconsumerization.techtarget.com/news/2240239514/Security-issues-lead-IT-to-block-Outlook-for-iOS|website=TechTarget|access-date=February 7, 2015|archive-date=September 21, 2020|archive-url=https://web.archive.org/web/20200921082311/https://searchmobilecomputing.techtarget.com/news/2240239514/Security-issues-lead-IT-to-block-Outlook-for-iOS|url-status=dead}}</ref><ref name=itworld-eublock>{{cite web|title=EU Parliament blocks new Outlook apps over privacy concerns|url=http://www.itworld.com/article/2881635/eu-parliament-blocks-new-outlook-apps-over-privacy-concerns.html|website=IT World|date=February 9, 2015|access-date=February 10, 2015|archive-date=April 24, 2017|archive-url=https://web.archive.org/web/20170424135557/http://www.itworld.com/article/2881635/eu-parliament-blocks-new-outlook-apps-over-privacy-concerns.html|url-status=dead}}</ref> Microsoft maintains a separate, pre-existing [[Outlook Web Access]] app for Android and iOS.<ref name=itworld-eublock/>