Drivers to message each other regarding real time job directions or instructions.

When drivers leave to job sites they have instructions gathered by our sales group or dispatchers on their ticket. As we know job sites change constantly from loader in a blind spot, a new ditch that wasn't there yesterday or to changing from heading in to job to backing in. There's times when we lose phone and radio service. If there's multiple drivers already en route, there's no way to notify them. The first driver would be able to send a message to the driver behind him. To simplify the messaging part for the driver there would be a variety of messages added by admin this would eliminate the drivers from typing.