The following is not about the Outlook Mobile app but about Outlook Web Access (OWA), also known as Outlook on the Web, when accessed using your mobile web browser.
A new look is available for OWA is now available and turned on by default, but you can opt-out at any time by switching the toggle.

Exchange administrator can manage the visibility of this toggle by updating the OWA policy using PowerShell:
Set-OwaMailboxPolicy “<outlook web access policy>” -OutlookBetaToggleEnabled $false
The new OWA UI on mobile browser looks nicer 
![image_thumb[1] image_thumb[1]](https://7552374.hs-sites.com/hs-fs/hubfs/Imported_Blog_Media/image_thumb1_thumb-83.png?width=133&height=244&name=image_thumb1_thumb-83.png)