One of the more common questions I get is "how do I ensure that only users who have a valid license can download updates?". This includes tasks like asking the user to enter a license key, sending keys to the update server, validating keys, showing license errors to users, and so on.

Currently, the update checker doesn't do any of those things. I'm considering implementing some license management features, possibly as a separate component that you can include only when your plugin or theme needs it. If this is something that you're interested in, please post your ideas and feedback below.

Here are some questions to get you started:

• What are you using to issue licenses, if anything?
  • Does it have an API?
  • If you don't have a solution for that yet, what are you using to sell the product (if it's something that's sold)?
• What are you using to provide updates, if anything?
  • What kind of API does it have?
  • Does it know how to check if a license is valid?
• What kind of information do you need to verify a license? Just a simple alphanumeric key, or a username/password pair, or something more complicated?
• How does the user enter the license key? Or, if you haven't implemented that yet, how would you like it to work?
• Why not use something like Envato, Freemius or Easy Digital Downloads?

I'm planning to leave this issue open for a good while to collect feedback and gauge interest.