While this issue appears to have been around awhile, or at least less popular
with older iPhones -- I don't doubt there are newer forces such as anti-gravity
fields and other micro-technologies at work to help levitate them now.
The ultimate plan would be to have the iPhone move the owner without walking.
But not just yet. The batteries would require much more power & be smaller.
The prototype may include field testing with two phones, worn like flip-flops.
So far, my iPhone 5C had to get a tether on his ankle, like those who are under
watchful eye of the law; he had a habit of trying to walk into the surf near cold
water beach out near our north gulf coast. Not a good place to dive in after him.
Due to hard surfaces all around, and this being prime earthquake country, he has
a case with rubbery padding is now permanently attached. Also has extra battery.
So there's no excuse, with an ankle tether & padded rain coat.
And he appears happy, in his storm coat with rubbery boots.
In the big city (100 mi away) we've seen newest iPhones with nice multiple-layer
protections to solve problems of iPhone sleep-walking or wandering off into lakes.
[Some of those 'marine cases' with mil-spec protections, look fine... but, 7-Layers?]
And some surfaces just aren't as flat &/or stable as we may think. A multiple story
building can move several inches when you're asleep. We don't take much notice.
Less so IF you're used to ignoring earthquakes less than 4 minutes & under 4.5M.
Next time your iPhone tries to take a hike off a tall table, give him a serious talking to.
Good luck with the care, feeding, and on-going training of your iOS buddy...😎