Post to custom page after submission

Hi,

Is it possible to add additional functionality after the form has been submitted?
Steps are as follows:

1. User submits the Gravity Form (and the entry is automatically saved to the database)
2. Form data gets posted to a custom page whereby the data is further validated and then posted to another script (on another domain) via CURL and JSON
3. The receiving script will return JSON data, with a "success" parameter of either true or false
4. Based on the "success" parameter, the Gravity Form Entry parameter of "registered_third_party" needs to be also updated to true or false
5. The normal "Thank you" response is displayed if successful or "Error" message if "success" was false

Is this possible?
Note that I am using the "Personal" License.

Thanks

Thank you David - looks good