Never ever bother your customers with plugin update notifications outside of WordPress.
Includes the full version of Secure File Download Class!
WordPress Plugin Update Features
- A fully featured update API for your custom or commercial plugins.
- Updates for your plugins are delivered right to WordPress’ update system.
- Security by expiring one-time download URLs.
- Check your users Codecanyon licence key.
Please your customers with this fully WordPress integrated plugin update API . No need to send update notifications via e-mail because everything is handled by WordPress.
Note: this item is intended for developers. You need some basic coding experience in PHP . But don’t be afraid, there is a good documentation included 
Updates
- 12.06.2011 – Completely rewritten the API + added support for newest version of Secure File Download Class.