The phone is a 6S but was powered off once I arrived at my destination Saturday lunchtime (fully charged from my drive) and I didn't turn it on again until Sunday morning, 8ish, when I was setting out to hike. It was completely dead. As I was car camping this time around I could have charged it back up but this would have taken up a good bit of my morning that I wanted to be out hiking, not screwing around with my stupid phone. Luckily, there wasn't really that much to take pictures of, but what if there had been?
And, I don't usually car camp, this was just a sudden whim as my company, in a rare act of generosity, gave us King's bday off. I'm thinking if my battery drained while my phone was off, an extra set of batteries or a new battery wouldn't do me much good. I know alkaline batteries are no good in the cold, so I had switched my headlamp batteries to lithium and had no issues with that.
I knew my canister stove would be difficult...I got it lit, but after 20 min of heating my two cups of water in my mug, the water wasn't even lukewarm. When it's 20 degrees and windy, it's certainly a bonus to have a hot breakfast! Oh well...next time.