I have measured few data points, except for infrared light which gives pretty weird results (low range) it seems to be fine. Probably infrared LED does not respond (it's not that obvious since my eyes cannot see in infrared spectrum).
It is powered by 9V battery, each time we power the device it registers single data point on the SD card.
It also is very comfortable, it fits my hand perfectly.
When I will solve the issue with infrared I will start gathering data points for machine learning as soon as possible.