- Cellfish, cellular phone selfish person: a person who is busy on their phone even when doing so is rude and inconsiderate of others around them (e.g.: talking on the phone while ordering at a restaurant)
- Cellphone drift: the drifting of a motor vehicle when the driver pays more attention to the phone than to driving
- Cellphone freak out: the brief frantic search that occurs when one thinks that they have lost their cellphone only to find it right in their pocket or hidden in the sofa cushion
- Cellphone novel: a novel written on a cellphone with the intent of it being viewed on cellphone screens only, so chapters can be read with little to no scrolling
- Cellphone Tai Chi: a series of movements while attempting to find cellphone reception, generally involves holding the cellphone in the air while simultaneously walking slowly in circles
- Cell-phonitis: a psychosocial condition characterized by inability to stop using or turning off the cellphone
- Cellular phone dermatitis: rash or an allergic reaction caused by direct contact with a component in the cellphone
- CPST, cell phone standard time: the time that all cell phones have
- Computer vision syndrome: eye and vision related problems that result from prolonged use of digital devices