Ability to sync my settings across devices.

Currently Outlook will only show iCloud calendars available on iCloud.com. It does not display subscribed calendars (such as work calendars, school calendars, etc), even if they are synced via iCloud to Macs, iOS devices, etc. The native iOS calendar app DOES show these calendars, as do other 3rd party calendar apps such as Fantastical. Please fix this.

For privacy and data usage

It would be extremely helpful to be able to attach files from other applications (at least other Microsoft apps) to an email. It is very inconvenient to have to transfer a spreadsheet or word document to Dropbox and then attach it to an email thread in order to save the integrity of the thread.

Currently it does not seem possible to remove events that have been cancelled by the meeting host. The update arrives in the mailbox but does not have an option to delete from calendar.

Being able to set up multiple "alerts" for a event/appt, etc. instead of just one on the calendar

It would be nice if you could create a Calendar Event from an Email, similar to dropping an email on the calendar in Outlook for Windows.

The Calendar Event would just need the Subject and body from the source email.

It could in the action menu, i.e. "Schedule, Move to Focused Inbox, Move, Mark Unread, CREATE EVENT"

Add a toggle that allows notifications which contain only the name of the email sender rather than a preview of the entire message similar to the approach used by the native Mail app and or Facebook Messenger. This prevents potentially sensitive information from being exposed to anyone within view of a phone sitting on a coffee table, etc.

Not sure if it's available to 3rd party apps, but the new Siri command in iOS 9 of 'Remind me about this' would be helpful. It basically takes what you're looking at on screen and creates a reminder for you.

I would like to be able to select which view pops up first when I first open up the app. I would like to make the calendar section the first thing I see.

As a heavy user of Gmail labels, is this the most important feature that I want, to make Outlook for iOS my default mail app.
Now you can only move a message to a folder.

It would be immensely useful to be able to access Office 365 SharePoint files in the attachments section.

When moving/filing lots of emails it can be a pain to have to scroll from the top of the folder structure every time rather than remember the last folder an email was moved to.

This is how it behaves in native iPhone Mail client and full blown Outlook when moving emails from Inbox

I need to have a way to sync my desktop Outlook calendar to my mobile Outlook App.

I put an event on the wrong calendar and can't move it.