Question

What is the “handoff,” and why was it a critical invention in the development of the cell phone?
Why does an American cell phone not work in Europe and other parts of the world?
Why are cell-phone innovations frequently introduced first in Europe and Japan rather than the United States?

Answer 1

In cellular communication handoff is a process of transferring an active call or data session from one channel to another.Handoff is also known as the handover.
Handoff is indeed important to prevent the loss of service to a caller.
American cell phones do not work in Europe and other parts of the country as American cell phones does not use GSM facility .Even if some phones have the GSM facility American cell phones and European cell phones have different frequencies.
There are more cell phone innovations are firstly introduced in China ,Japan compared to US because because these countries spend more for the research and they are more expertised.