I was going thru SharePoint 2013 API development guidelines from Microsoft and found following table which provides
guidance on which set of SharePoint 2013 APIs for common SharePoint 2013 development project scenarios.[Source: http://msdn.microsoft.com/en-us/library/jj164060%28v=office.15%29#CommunityContent]
| If you want to do this ... | ... use these APIs |
|---|---|
| Create an ASP.NET web application that performs create/read/update/deleted (CRUD) operations across a firewall on SharePoint data or external data that is surfaced in SharePoint by a Microsoft Business Connectivity Services (BCS) external content type | JavaScript client object model |
| Create an ASP.NET web application that performs CRUD operations on SharePoint data or external data that is surfaced in SharePoint by a BCS external content type, but does not have to call SharePoint across a firewall | .NET Framework client object model, Silverlight client object model, or REST/OData endpoints |
| Create a LAMP web application that performs CRUD operations on SharePoint data or external data that is surfaced in SharePoint by a BCS external content type | REST/OData endpoints |
| Create a Windows Phone app that performs CRUD operations on SharePoint data | Mobile client object model |
| Create a Windows Phone app that uses the Microsoft Push Notification Service to alert the mobile device of events in SharePoint | Mobile client object model and the server object model |
| Create an iOS or Android app that performs CRUD operations on SharePoint data | REST/OData endpoints |
| Create a .NET Framework application that performs CRUD operations on SharePoint data | .NET Framework client object model |
| Create a Silverlight application that performs CRUD operations on SharePoint data | Silverlight client object model |
| Create an HTML/JavaScript application that performs CRUD operations on SharePoint data | JavaScript client object model |
| Create an app for Office that works with SharePoint | JavaScript client object model |
| Create a custom Windows PowerShell command | Server object model |
| Create a timer job | Server object model |
| Create an extension of Central Administration | Server object model |
| Create consistent branding across an entire SharePoint farm | Server object model |
| Create a custom Web Part, application page, or ASP.NET user control | Server object model |
