Depends also on the phone. I have this ancient iPhone that basically doesn't have a battery because a day's charging lasts it about thirty seconds or so. I've resorted to keeping it plugged in all the time, which works fine as it's still able to make and receive calls that way, and I can't see myself ever trying to do anything else with a phone. As an upside, I can always ignore people and then use the excuse that I wasn't near my phone at the time. It's basically all the convenience of an old landline, in the shape of an uncomfortably small and unwieldy little block.