hjulenissen mentions the tiny 1" sensor Sony RX100 series. These have been incredibly popular among those long-distance hikers (especially through-hikers doing greater than 1 week long hikes) who can afford them. When ounces / grams are counted, and when the hiker wants more than a phone or tablet, the Sony RX100 is mentioned. That being said, the phone or tablet is also a map display device, ebook, alarm clock, naturalist ID manual (I have a North American bird app and a star map on my phone), low-level GPS device (only for areas with cell service - the true GPS devices operate from satellite signals), yep - phone and internet when in cell service range, and camera. So I expect a lot of people are going to just use their phone/tablet with the now-much-improved on-board cameras.
I confess that I have looked longingly at the RX100 series for an always-in-my-pocket camera for casual and street photography. And of course I have looked longingly at the A7Rii - but first I have to upgrade my computer and storage to deal with the much bigger files. I keep hanging on hoping for news of the next MacBookPro with the Skylake or Kaby Lake microprocessor (cooler running, uses less energy than current Haswell and way less than my i7 Nehalem-generation processor laptop with non-retina matte screen). That's OK, I enjoy using Canon 6D currently. Ergonomics are Just Right For Me. I don't need no stinkin' 61 AF points, I manual focus a lot. I am not through-hiking any time soon, that's a retirement gig.