***Note this post applies to Power BI for Office 365 (deprecated as of 12/31/2015). Though some concepts remain the same or similar, all details are not necessarily applicable to the new Power BI V2 service.***

There are multiple ways to view content published to a Power BI site.  Four are mentioned below.  These screen shots were taken during the Public Preview of Power BI (during which I cleverly called my site “PowerBISite”).

Power BI Site

The Power BI Site that we see in the first screen shot is an app that was installed from the SharePoint Store when the site was initially provisioned and set up.  Apps are considered “mini applications” which add and extend functionality.  Even though this view is using the app, I haven’t seen where it’s typically referred to that way (i.e., because the mobile app is the one called Power BI App).  This view seems to be typically referred to as the Power BI Site.

The Power BI Site is what I’d expect most users and report consumers will prefer to use because it offers the thumbnail previews.  Think of this as the front door.

My URL for the Power BI Site in the USA is as follows:  

https://sites.powerbi.com/sharepointpages/SPIntegration/PowerBI/pages/PowerBI.html?languageLocale=en-US&regionalLocale=en-US&SPHostUrl=https://TenantName.sharepoint.com/SubsiteNameIfApplicable

Power BI Site Home Page

The home page for the SharePoint Online site looks like the next screen shot before it is customized.  In the Public Preview, this is where navigation takes me if I click the “Return to SharePoint” hyperlink in the top right-hand corner of the Power BI Site (i.e., the screen shot shown above).  This home page is where you can access the Page properties via the ribbon.

The URL for this page is:  

https://TenantName.sharepoint.com/SubsiteNameIfApplicable/_layouts/15/start.aspx#/SitePages/Home.aspx

Power BI Site Document Library

There’s also the document library itself.  You can think of this as the traditional “All Documents” view of the first screen shot above – just without the thumbnail previews.  Same content, just a different entry point.  This is where you can get to the File and Library properties via the ribbon, so this view will be useful occasionally.

Think of this as the back door.  The first screen shot above is an endpoint which allows access to this document library.

The URL for the document library is:  

https://TenantName.sharepoint.com/SubsiteNameIfApplicable/_layouts/15/start.aspx#/DocumentLibraryName/Forms/AllItems.aspx

Power BI App (aka Power BI Mobile App)

Last but not least, there’s the Power BI App (aka the Power BI Mobile App) which can be downloaded from the Windows Store.  If you hear someone refer to the “Power BI App” most likely they are talking about the Mobile App and not the browser-based Power BI Site (i.e., the app that was initially installed from the SharePoint Store).

Just a sidenote:  A “Featured” report in the browser-based Power BI Site (first screen shot above) isn’t the same thing as a “Favorite” report. Featured reports appear at the top of the Power BI app page, whereas Favorite reports appear in "My Power BI" which is your personal set of reports.  At this point, Favorites in the Power BI App (browser) are not sync'd with Favorites in the Mobile App. I hope that happens at some point.