National's key markets included wireless handsets, displays and a variety of broad electronics markets, including medical, automotive, industrial and test and measurement applications.
A large number and variety of "emoji" and "kaomoji" are available on handsets.
Since the 1920s, handsets usually also contain the phone's transmitter (microphone) which is positioned close to the mouth.
Such battery-backed devices typically are designed for use with analog handsets.
Since the handsets were all supplied by the telephone company, most had the same shape, simplifying the physical interface.
The company, founded in 1997, specialises in the development, publishing and distribution of games for mobile handsets.
Old handsets manufactured before 1985 using a carbon microphone transmitter are not sensitive to polarity.
Random handsets can be used with random transceivers, but some mismatches may result in unusable functions.
