cell phone vs radiotelephone

cell phone

noun
  • A portable, wireless telephone, which changes antenna connections seamlessly during travel from one radio reception cell to another without losing the party-to-party call connection. 

radiotelephone

noun
  • a device that allows two-way communication via radio 

verb
  • To communicate via such a device 

How often have the words cell phone and radiotelephone occurred in a corpus of books? (source: Google Ngram Viewer )