Usually my iPhone ends the day at 60%+ battery but today it was at 12% when I got home. I checked Macrumours and noticed that Apple had an outage. I'm guessing it might be the iPhone constantly trying to ping iCloud which led to the drain.
Yes, mine tanked at some point in the late afternoon/evening. Same basic routine as any other weekday, but the phone was probably 20% lower battery by the end of the night than is typical.