My husband didn't do digital calendars, so it was paper or nothing. I use a digital calendar all the time at work. I decided I'd go with the joint paper calendar at home, and only put home stuff on the digital calendar if it was going to affect what I did at work. I rarely double book. I tend to check both calendars for the forthcoming week anyway, so usually spot if there is a potential clash before it actually happens.
Now my husband has passed away I have continued with the same system - I quite like keeping work and home separate.