AC-U-KWIK is a subscription-based app that allows the user to install it on only 2 devices. In order to enforce this business rule, it uses Api.acukwik.com, a business facing site that allows admins to manage the subscrriber’s devices. The site is secure, but you can view it here.
To accomplish this, the website exposes an API that is used by the app to determine if the user is valid and tracks how many devices that user has installed the app on. There is also a simple interface to allow admins to manage devices for users who have reached there limit or have changed their login ID:
There is also a feature that allows a company to purchase a block of subscriptions all with a common login which simplifies administration.
The site is build on a “MEAN” stack, which includes the Mongo database, Express and Angular frameworks and Node as the web server.