Have you tried mounting your phone on a tripod? A lot of people here don't know what they're talking about, no offence.
You need a bracket to mount the phone onto a tripod and considering how large and odd the button placements are, many times you need a proper bracket.
Putting a tripod in sand is another retarded cope, unless this wasn't from a nudist beach which wtf were they doing? Anyway, people typically place CDs under the tripod so it doesn't sink into the sand.
Then there's also the logistics about carrying a fucking tripod to a trip with a significant other. Unless both of you are photo slobs, the other will absolutely NOT like that, speaking from personal experience. Most just bring a dumb stick to mount a phone on.
Simplest and least logistically retarded thing to do would involve a friend and then cropping the photo, that's it.
Phone levels are useless.