You can switch accounts using the Account Picker. The account picker allows the user to choose from the accounts your user has permission to view. To change accounts Simply select the "Settings"
Located in the upper right of the window. A menu will pop up choose Switch Account.
You can search for an account by tapping in the “Search Accounts” edit box and type in the acct, or you can scroll through the list.
The account list updates as the user types, and the keyboard is hidden by tapping the magnifying glass icon.