User1120430333 posted
WebAPI is more widely used now, becuase WebAPI uses the MVC pattern, it's HTTP only and the default data exchange is Json. WCF Rest is XML based on the data exchange, but it uses more protocols like TCP, HTTP and UDP.
From what I understand, anything over HTTP is text based, and WebAPI would be slower than using WCF Rest over TCP and using binary with binary being the fastest means possible in data transmission.
The link should help you.
http://www.compilemode.com/2015/06/difference-between-web-api-and-wcf-rest.html