Reroute all WordPress mail through Postmark to increase email reliability.
This plugin replaces WordPress' internal email sending functionality by routing all email through Postmark, greatly enhancing email reliability. If you rely on your WordPress install to send you email, this plugin along with the awesome service from Postmark makes sure that it actually does reach its destination.
Why you should use this plugin over the official Postmark approved plugin or other Postmark plugins?
More info about the plugin: