Fellow Galaxy M51 users - is this the kind of usage you get out of its 7000mAh battery? I've read that a lot of people easily get more than two days even with medium/heavy use. My girlfriend's A21s seems to be doing as well as (if not better than) this even with its 5000mAh battery.
I think this is just an estimate. My M51 currently says 1d 14h left at 77%. I just use it as a spare device on WiFi currently but do use it moderately and it easily lasts several days. I've found the battery life to be brilliant