Sending RESTful API from WordPress

Hi there!

What plugin did you try using?

I’m not sure if you follow core development but there will be a REST API introduced in the upcoming 4.4 and 4.5 releases of WordPress. They do a pretty good job of keeping people in the loop:
https://make.ww.wp.xz.cn/core/2015/11/11/wordpress-4-4-field-guide/

That particular post is outlining some of the key things coming in 4.4 that will be released in December.