Hi @jespa007, thanks for your query and glad to know you are interested in developing with the Eye Tracker 5 🙂
You will be pleased to know that we produced a tutorial providing detail in getting up and running with the Stream Engine API which you can view @
With regard to analytical data, if your intention is to develop a project that stores gaze data for research or analysis, then you are legally obligated to purchase a special licence from Tobii for this purpose.
You can read more about this @ https://developer.tobii.com/license-agreement/
Once acquired, you should be able to use the Tobii Pro SDK which exposes further metrics such as pupil data, 3D eye position, etc.
Please do let us know if we can provide any further information. Best Wishes.