What is the mass noun of cellphone?

There isn't a single perfect mass noun for "cellphone". Here's why and some options depending on context:

* Cellphones aren't a homogeneous substance: Unlike flour or water, cellphones are individual, complex objects.

* Context matters: The best word depends on what you're describing.

Here are some possibilities:

* Technology: "There's a lot of technology in this room." (Generalizing about the devices)

* Electronics: "The store had a huge selection of electronics." (Focus on the technical aspect)

* Devices: "They confiscated all the devices at the exam." (Broad term for any kind of electronic gadget)

* Communication: "The lack of communication was frustrating." (Referring to the function of cellphones)

Note: Using a plural noun like "cellphones" is usually the most straightforward way to refer to multiple cellphones.