There have been a few threads on the different social networks around the rename of the “App Model” to “Add-in Model” for Office 365.
The reasons behind this change can be summarized as such:
- Confusion across Microsoft’s product range as to the exact meaning of the word
- Negativity from the Partner Network over the perceived meaning of the word
Tenancy – A SharePoint tenancy is a set of site collections that are configured and administrated as a unit.
In SharePoint Online, when a new customer establishes an Office 365 account to host its SharePoint sites, the Office 365 environment creates a new tenancy. The customer’s business users that access the tenancy are known as tenants.
So what is an App Principal? This is probably best explained by way of a little story, and it goes something like this. Suppose I have a SkyDrive site. I keep all of my documents and pictures up there. When I want to access that content I have to enter my username and password. SkyDrive validates my credentials and then gives me access to that content.
While developing apps for SharePoint 2013, you might be wondering about the host web and app web terminologies.
The Host Web is nothing but the SharePoint site where the App is actually installed. In other words, all the resources accessed by a SharePoint App has to be deployed in a different sub-site, named as the App web. And, the actual site where the app is deployed is called the Host Web.