Action Button for recording quickly and discrete.

Needs to be a way to long hold the volume button or something similar in order to activate the recording feature. In example; phone is in your pocket or under table, you don’t have to unlock the phone to begin recording conversations. I am currently in an medical ICU care unit as a patient and have multiple doctors and medical staff in and out telling me things that others need or want to know but I can’t always remember the verbiage and descriptive conversations I have with each person and it becomes a nightmare trying to get things done.