Recently released is a Windows Desktop application that allows you to access your QuickBooks Online Company file on your desktop. You will still need an internet connection and an active company file. The application is free to download, I will post a link to the Intuit Blog which describes the application in more detail and has a download link. The application is free to download and I strongly encourage QBO users to try out the application.
The benefits of using the desktop application rather that using an internet browser really boils down to ease of use and convenience. I personally noticed an improvement in speed while using the application versus the browser. Also those of you that are accustomed to using the tradition Desktop versions of QuickBooks (Pro, Premier and Enterprise) will be happy to be able to use the drop down menus to access your reports, transactions and other common areas in QBO.
The following is a link to the blog post and download link.