Hi,
You say bus ... does this mean there are predefined routes (in opposite to random driving across the land)?
If so, it's far more easy.
Just make a list of the town's names and their coordinates.
Then compare the actual bus coordinate with the town coordinates and find the nearest town... display it's name.
If your list of towns is in the correct order of the bus route, then finding the next town is even easier.
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You may add additional informations to the display, like distance to the next town, expected arrival at the next town, street(location) of bus stop, bus stops automatically or only on request...and so on.
Klaus