How do smartphones work?

 This is written fairly simply for the average person by the way.

There are two basic inventions that allow smartphones and cell phones to work. 

They are Digital Sound and Global Positioning Satellites. Of course there are many other things that allow Smartphones and cell phones to work but these are the two basic ones.

GPS or Global Positioning Satellites were invented because magnetic North and South were moving and still are so fast it was causing jet planes (especially fighter jets) to run into each other. So, they started sending up global Positioning satellites in a geosynchronous orbit (which means they stay relatively stationary above a particular part of Earth. This allows triangulation between three satellites and any location on the earth  anywhere.

Next Digital Sound is something much easier to boost because of it's very nature. So, when it gets too low in sound (the digital part) it can be reboosted up to where you can still hear it or re-amplified globally.

Then the two of these things allow the satellites to find your phone and connect it to any other phone on earth under most circumstances except for Solar Flares and other things like this which might temporarily or even permanently end all electrical technology in that area of earth or another thing would be a nuclear blast might permanently destroy all cell phones and all smartphones and fry all electrical circuits of anything in that location so nothing existing technology wise on the ground there would ever work ever again. 

So, at that point new techonology would have to be brought in from other locations on earth not technologically destroyed by a Solar Flare or a nuclear blast in that particular area of earth.

So, in a nuclear blast no cars or motorcycles or electric bicycles existing there when this hit would ever work again. The same would be true of all smartphones computers and tablets of any kind and all cell phones. 

This is why backups on non-magnetic media are very important like DVDs and CDs or else everything could be lost information wise permanently in a solar Flare or  Nuke hitting your area if you are above 10 or twenty feet below ground. If you are underground deep enough the solar flares and nukes would not affect your technology which is why they have places like Colorado Springs where the Air Force is completely in man made caves underground.