Without Global Positioning Satellites Cell phones could not work

 There is something called a "Ping" which simply means something like a Microwave tower "pings" your cell phone to see if it is on. If it is on it is consdered able to receive or make a call. The next "layer" is that your signal is digital not analog in your cell phone. This allows your voice as it digitally goes out to be amplified more easily from a digital signal. This is true for the phone you are talking to also. 

When you call a number on your phone or text someone your phone says to the Microwave tower nearest you: "Find the number I just dialed." Then the request goes out to wherever that number can be found if the phone is on (usually in the U.S.) but it also could be anywhere on earth too. Once contact is made with the phone someone calls on a cell phone the signal is sent to the nearest Microwave tower of that Cell phone wherever it is on earth and connection is made and people can talk or text or whatever they want to do.

So, the two technologies primarily (besides Microchips)  and special rechargeble batteries that allow cell phones to actually work worldwide are GPS locators and Microwave towers working in harmony and digital conversions of voices to 1s and zeros worldwide. Then also the internet on smartphones works similarly but usually uses a form of HTML (Hypertext markup language) like most computers of various kinds including laptops and Ipads and the like use too. So, the internet on a smartphone works a lot like it does on other computer devices too.

I also looked up "Ping" and saw something called "Ping Test" there. However, I'm not exactly sure who uses these "pings" besides telephone companies of one sort or another through their microwave towers to tell if phones are turned on or still turned on and such.