The Mobile devices tab lets you view all the devices that you’re currently using to synchronize with your mailbox. If you’re using a POP or IMAP email program to synchronize your email, that will also appear in the list.
You don’t use Outlook Web App to specify the devices you want to synchronize with your mailbox. Instead, devices that you connect to your mailbox are displayed as connected devices within Outlook Web App after you’ve created a connection to your mailbox.
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