Yes having to scan you bill/receipt is the approach I am thinking of but how are providers/supermarkets willing to give this data? or I have to find away to get these information somehow.
As I wrote in another comment, I would like to know how many are interested on this idea to see if the journey is worth to take.
As I wrote in another comment, I would like to know how many are interested on this idea to see if the journey is worth to take.