Get list of available updates I need to be able to easily get a list of available updates for a site.

I've come across the update_get_update_list() function, but that only returns an array of " information about database updates that need to be run, and any updates that are not going to proceed due to missing requirements." I want the list that gets displayed on the admin/modules/update page, but can't seem to find any way to do that through the core update module, and want to avoid using grep on a drush up -n call (as that feels kind of hacky.)
As far as I'm concerned there are three ways you can achieve this:


You can use the Drupal UI /admin/reports/updates 
You can use Drush drush ups
You can use a Third Party Service Drupal Status. 


I wrote an article that explains how to integrate multiple Drupal website with Drupal Status.