Yoast License Manager
This library will take care of the following.
- Managing license related options
- Setting license key from a constant
- Obfuscasting (valid) license keys
- Remote license activation / deactivation
- Checking for plugin or theme updates
Usage
Inside Plugins
A sample plugin is included, have a look at its source.
Inside Themes
A sample theme functions.php file is included, have a look here.