Mobile radio.

For most mobile use, you will just need a radio with the minimum controls.

Any mobile radio should have the minimum requirements (volume, squelch and channel change). Any more than this may be difficult to use while on the move, and may even distract you while driving.
Another consideration for mobile use may be the size and shape - it should fit into a space somewhere in the vehicle, where it can be seen and reached easily. If the radio will need to be mounted high up or at a distance from the driver, channel change buttons on the microphone may be helpful.