If you are the least "into" photography, bring a decent DSRL and your phone.
My old Nikon D80, for some reason, started making pictures worse than my phone, so I borrowed my daughter's Canon with a couple of lenses.
IMO, having the ability to take good quality ZOOM and landscape photo is wonderful.
I always carried my phone, but if there is a second person (in my case, my wife) who can take a decent DSLR with a couple of lenses or just an 18-135 lens that can make a world of difference.
With my phone, I could take this type of thing (basically, a "snapshot"):
Which might be all you would want, and that is fine.
With a low-end DSLR and decent lens, you can get this type of picture, which is almost impossible with any phone I've ever used...
Not that, a "fair" picture of a small monitor lizard would make the cover of National Geographic, but a zoom lens and a decent camera can add a lot to a "journal" of your trip.
Of you are into photography, a camera makes for a much better photo log of your trip, than a bunch of phone "snapshots."
The camera companies better be quick, or phone technology may catch up with them soon!
Even if my wife were not with me to do photography, I would take along a camera to take pictures during downtime.