I cannot see a lot of difference between reading a newspaper, a detective story, a holy writ, an operations manual, a technical manual or an MEL in the cockpit.However, as a frequent offender, I have to say that I do think that stock market tracking, spiritual solace and base check preparation belong rather more on the ground than in the air.
These days, commercial radio is available on most airborne Coms boxes. A low volume classical selection on box 2 still allows for SELCAL or call sign recognition and, whilst relaxing the troubled soul, permits the brain to stay on track and the eyeballs to roam.
