Blighty

This plugin monitors installed WordPress plugins on your installation. It notifies the admin (or other email) when updates are available. Plugins can be excluded from monitoring.

Blighty Pluginator

This plugin monitors installed WordPress plugins on your installation for updates and notifies via email when they are available.

Gary Pendergast

Advanced Automatic Updates adds extra options to WordPress’ built-in Automatic Updates feature. On top of security updates, it also supports installing major releases, plugins, themes, or even regular SVN checkouts!
If you’re working on a WordPress Multisite install, it will properly restrict the options page to your Network Admin.
While this will be useful for the vast majority of sites, please exercise caution, particularly if you have any custom themes or plugins running on your site.

Advanced Automatic Updates

Nice Plugin

Adds extra options to WordPress' built-in Automatic Updates feature.

Blighty Pluginator vs Advanced Automatic Updates