How many of wonder that we can easily convert the asp.net application into SharePoint 2013 using Visual Studio 2013. The wizard does the conversion for you. The steps are outlined below:
  1. Open the Asp.Net Application in Visual Studio 2013.

  2. Right-click the asp.net application and choose “Convert” then choose “Convert to App for SharePoint Project”.

  3. The wizard will ask for the SharePoint URL to deploy.

  4. Provide the valid URL.

  5. Give the Trust it option when Trust window opens.

  6. After the Successful conversion, Asp.Net application will open from SharePoint URL.
Happy SharePointing