From what I can tell, it will be locally hosted, and non-cloud dependent. Don't know about the open source though (we can guess not).
Regarding the second part of your comment, an EEG device like that will have access to way less information (even with state-of-the-art signal processing techniques) than, say, an Apple watch or a FitBit, which have access to tons of biometric information (pulse, ECG, sleep data, constant geolocalization, living habits + much more if you also upload your weight and blood pressure measurements in the companion app), yet the vast majority of the public didn't seem to be too preoccupied when those came out.
Regarding the second part of your comment, an EEG device like that will have access to way less information (even with state-of-the-art signal processing techniques) than, say, an Apple watch or a FitBit, which have access to tons of biometric information (pulse, ECG, sleep data, constant geolocalization, living habits + much more if you also upload your weight and blood pressure measurements in the companion app), yet the vast majority of the public didn't seem to be too preoccupied when those came out.