I’m personally interested in biofeedback devices which could connect to smartphones (e.g. vs BT4.0) and which could be used for stress management and meditation assistance during a daily activity.
I don’t think that smartphone’s built-in sensors are good for these purposes.
Regarding PIP which you mentioned and which uses GSR - I don’t like the idea of holding something between fingers - this is not convenient and makes this device just a toy (IMHO). Armband strap would be better… Do you know such projects?
Another field are EEG devices. I ordered Muse just today; there is also Melon which got funding, they promise to release it this year… And EMOTIV which got funding as well (though I don’t like the pictures - the device seems too bulky). Will see…
If you have any practical suggestions - let’s discuss. I’m interested to support and participate in developing of new generation devices like these. But only if we have something concrete to discuss