Subscriptions Communication to REST API

Hey guys....

I want to implement unlocking features for the application. I understand this is done by using Custom license fields. But what I don't understand is how to unlock the feature if I already pre-populate the serial number. Here is what I'm thinking:1. Customer purchases a plugin to unlock features2. A serial number is sent to them as a general use for the software3. As the user adds more plugins, then my server should send some type of file to activate the feature.

Here is the part I don't understand...what if the user gets a refund or if I want to stop the feature, I change the status of the purchase to 'Unpaid.' The server then sends an update to the server...

I guess what I'm asking is if I want to automate subscriptions and/or features between the order status of my php shopping cart and have that ability to turn off and turn on subscriptions, how is this achieved?

Well, the custom license fields article is a pretty great place to start: http://wyday.com/limelm/help/license-features/

A product key can have as many custom license fields as you need. And you can change them at any time (meaning a customer can buy new features of your app, or you can revoke features of your app).

And all of this can be controlled via the web API: http://wyday.com/limelm/help/license-features/#web-api

Ok, I see.....

Here is another issue. The software of which I am selling plugins/addons to is free. So that means I have to provide a serial number activation to a free product. So I'm paying for a ton of activations for a product that is free.

Is there a way that I can activate addons/features for a product, but without providing an activation?

I don't understand the "free" part. Aren't you selling your product? Or is this just a trial of your app. If it's just a trial, then use the verified trials: https://wyday.com/limelm/help/trials/#verified

There's a ton of verified trials included with every plan.

Also, you only need one product key per user or per machine, if that's how you want to do it. You can then associate as many custom license fields as you want with that key.