e938ed2d_SharePoint_Server__2007__2010___SharePoint_Farm_Solution
[0] Integration with Other Apps [Sandboxed Solution] Similar to Farm Solutions. [Apps for SharePoint] Multiple options for the integration from Services to actually implementing a fully customized applications against different products SDK as this is technology independent. We can consider a server in the SharePoint farm, an external server such as a server in the cloud, a client computer, and a mobile device. [SharePoint Farm Solution] 
Limited options and need to use BCS (Business Connectivity Service), Web Services.
A Point For Sharing On SharePoint Server (2007, 2010)
SharePoint Farm Solution