A device and a method for determining a transactional device used for a transaction. More particularly, the device includes a data processor, a memory, an optical sensor, and a set of transactional interfaces. The method includes: obtaining at least one recording coming from the optical sensor), the recording being obtained when a user holds the transactional device in hand; determining at least one confidence score, the at least one confidence score being associated with at least one corresponding input of a structure of data for activating transactional interfaces present within the electronic device; and activating at least one transactional interface associated with the at least one input as a function of the at least one confidence score.