We do provide a server to server callback. You can specify the endpoint you want us to notify with that callback after the completion of a rewarded video for each app in the Manage Apps section. Our server to server callback has a slightly different implementation than other providers and here are the important differences:
1. Our server to server callback never goes through the user's phone. After our SDK notifies us that the rewarded video has been fully watched and all other client side processes have been completed, our SDK notifies our server and our server then goes directly to the endpoint you specify. This means that the user can not hack callback to fraudulently rewarded themselves so long as you use a unique endpoint in the Manage Apps section.
2. You can specify which variables (like currency type/amount, user device IDs, etc.) you'd like to receive in the server to server callback. These are listed in the Manage Apps section also.
3. Because our server to server callback does not ever pass through the user's phone and goes from our servers to yours, we do not support any secret hash or other encryption methodology since the user can never intercept the callback.