Stanislav Khromov

This plugin provides JSON and XML output formats for Toolset Views.
The plugin will also fetch all available custom fields for each post, making it truly simple to integrate WordPress 
with other systems that speak JSON and XML.
New in version 2.0
This plugin now supports Taxonomy and User queries!
Usage
Basic usage
Create your View, go to Settings -> Views Output Formats and pick your format. You will get a link to the XML or JSON version of the query.
<h3>Requirements</h3>
<ul>
<li>PHP 5.3 or higher</li>
</ul>
<h3>Translations</h3>
<ul>
<li>None</li>
</ul>
<h3>Upcoming features</h3>
Support for attaching taxonomy data to posts is planned
Feel free to contribute over at GitHub: 
https://github.com/khromov/wp-views-output-formats

Views Output Formats

Export your WordPress data in XML and JSON formats easily!

digitalzoomstudio

This plugin creates a custom wp_query via a shortcode. Accepts any parameter of WP_Query – https://codex.wordpress.org/Class_Reference/WP_Query
Demo here – http://digitalzoomstudio.net/developer-freebies/
My premium plugins – http://bit.ly/nM4R6u

DZS Custom WP Query Shortcode

This plugin creates a custom wp_query via a shortcode. Accepts any parameter of WP_Query

Views Output Formats vs DZS Custom WP Query Shortcode