I usually keep my wireless appliances at at least half before I put them on the charger again. Never know when I'll need to suddenly run out of the house and not make it back for another two or three days, and I'd like to make sure my things have enough juice to last until I can recharge them again in an unexpected situation. Also I have a solar charger with multiple different usb hubs and adaptors for all the things I usually keep with me in case I need to set up a camp or something. Not like I'd ever need to, but y'know. Be prepared and whatnot.