To calculate your 2-D position (latitude and longitude) and track movement, a GPS receiver must be locked on to the signal of at least 3 satellites. With 4 or more satellites in view, the receiver can determine your 3-D position (latitude, longitude and altitude). Generally, a GPS receiver will track 8 or more satellites, but that depends on the time of day and where you are on the earth. Some devices can do all of that from your wrist.
The first smartphone was developed by IBM and BellSouth, which came out to the public in 1993. Althought basic compared to todayâs standards âSimonâ had a touch screen that was capable of accessing email and sending faxes. Smartphones are major extensions on normal cellphones.
Dr. Martin Cooper is the person credited with both inventing the modern cell phone as well as making the first cell phone call in New York City, New York in April 1973. A related invention is the cave radio phone invented by Nathan Stubblefield who was awarded a patent for the idea in the early 20 th Century (1908).Since his work does not provide the technology behind modern cell phones, he is not given credit for inventing the cell phone. related invention is the cave radio phone invented by Nathan Stubblefield who was awarded a patent for the idea in the early 20 th Century (1908). Since his work does not provide the technology behind modern cell phones, he is not given credit for inventing the cell phone.