We still have the paid, unlimited tier offering but the golden difference between the free and paid versions is a little marketing push. All we ask for the free tier, is a simple logo + link be displayed on the website or application currently being protected by Cordon. This might entice more people that are willing to pay for the service to the platform, while also increasing the install base and thus spreading the protection even further around the globe.

At one point, this was going to be a forced banner that is displayed on top of successful requests after the 10,000 hit limit was reached. We could implement it in our access code that ran on the application server, but it would be trivial to disable the line of code. We could combat the editing of code, but that would mean the free version would have a different set of requirements than the paid version (say by using something like IonCube to obfuscate client-side PHP code). On top of client-side requirements, we'd have extra requirements in the packaging of our code and the delivery to customers. This was decided against, since the core of the product is a REST/JSON API and we would have to support every language our customers wanted to use for the access code.

The next idea was to track the usage, to see if anyone did indeed try to remove the banner, which evolved into simply asking people to display a logo or upgrade to the paid version. Psychologically, this presents itself as a barrier to continuing, a proverbial fork in the road – but also something that must be completed for closure. Customers are more likely to pick a path and stick with it and be happy in their decision if they have a control over the outcome and creating peace of mind is what this product is all about, so it seemed like a good fit. I think it's more than fair to ask for a link in exchange for a free product and hopefully our users will too.

Now the only problem is: what happens if people abuse the honesty-box system and fail to display the logo on their website? Well, ultimately this is something that is a little easier to manage – we don't need a team of collections agents calling customers that haven't paid, we just need to have someone at the office look do a few spot checks here and there. If it's discovered a customer has used a free key without following the rules, we issue a quick reminder to do so. If there's blatant disregard for the policy, we can then move to ban the key from our system.