smartphone vs cellphone

smartphone and cellphone both are nouns.

Word	Noun	Adjective	Verb	Adverb
smartphone	Yes	No	No	No
cellphone	Yes	No	No	No

As nouns, cellphone is a hypernym of smartphone; that is, cellphone is a word with a broader meaning than smartphone:

smartphone: a mobile phone with more advanced computing capability and connectivity than basic feature phones
cellphone: a hand-held mobile radiotelephone for use in an area divided into small sections, each with its own short-range transmitter/receiver

Other hypernyms of smartphone include cell, cellular phone, cellular telephone, mobile phone.

smartphone (noun)	cellphone (noun)
a mobile phone with more advanced computing capability and connectivity than basic feature phones	a hand-held mobile radiotelephone for use in an area divided into small sections, each with its own short-range transmitter/receiver