While this is trivial for some people, it is extremely difficult to infeasible for others.

Taking advantage of people's passive integration of sensory input into their perception of the world around them seems like a reasonable aid for people who have difficulty with things of this nature.

You people, some SV quacks could come up with a device that sends you a tweet when you need to take a shit and you'd still be telling me how it's making the world a better place.

Some people do end up with nerve damage that impairs their ability to know when they need to empty their bowels. What you describe may indeed be useful for them.

I was in New York a short time ago, and though I was outside, in daylight, I had absolutely no sense of direction. I came out of the wrong exit from Grand Central, and had to pull out my phone's compass (after reviewing the map) just to get a sense of which direction I had to go.

It's still very easy to lose your sense of direction in unfamiliar territory, even when you're paying attention.