Is Free API calls possible to BOX

As a service I need to scan files on box of Users. Since I will exceed the API limit under the quota given by Box as per purchase. My Client informed me the api calls made form Apps in Box integration are free. 

So, Is it true that If I make API calls from the clinet-id and client-secret that of APP published by us and added by our client will be free. Will this not be counted in quota.

Since plan supports 100K API calls and can I make >100K API calls free.