Do you think they haven't assumed such a device exists?

Similar devices and applications already exist, particularly on smartphones like the iPhone.

How could serfs have a matter transmitter, even if such a device existed?

Very few devices with this capability exist, possibly due to content copyright restrictions.

And Peter was convinced that no such device could exist.

Nuclear devices had existed for over a century, and only four of them had ever been used in anger.

More exotic devices with multiple electrical gates do exist in the literature.

If good devices existed, they would help her be independent.

Technology is seductive; when a device exists, we feel compelled to own it.

No one except for a few officials knew that the mechanical device existed at all.