Note The name "apps for SharePoint" is changing to "SharePoint Add-ins". During the transition, the documentation and the UI of some SharePoint products and Visual Studio tools might still use the term "apps for SharePoint". For details, see New name for apps for Office and SharePoint.
SharePoint client APIs
You can use the SharePoint client object model to retrieve, update, and manage data in SharePoint. SharePoint makes the object model available in several forms.
.NET Framework redistributable assemblies
Windows Phone assemblies
Silverlight redistributable assemblies
For more information about the sets of APIs that are available for SharePoint, see Choose the right API set in SharePoint.