Microsoft updated its Office for iOS such that Outlook for iOS opens Office documents sent as attachments directly in their respective apps.
Files sent as attachments in Outlook will open directly in Word, Excel or PowerPoint. This makes files ready for editing faster and more easily.
Open attachments right from Outlook
The text below the files indicates the app needed to open the file. If an Office app is not installed, Outlook opens the file in a simple viewer and provides a link to the App Store.
Collaborate with attachments in email
Reverting to a mail with changes to attached files is made simpler. Editing an attached file and a tap on the Back button closes the document and returns you to Outlook, automatically adding the now-updated file as an attachment in your reply.
Sending attachments with Outlook
Word, Excel and PowerPoint now include a “Send with Outlook” option in the “Share” menu.
Read more here : Deeper integration between Office documents and Outlook for iOS