I've used map-drop to clone google map route creator. When client enter the aplicaton, he get the flowing message:
If client dicline and don't provide location move to the defualt position - Tel-Aviv. Otherwise, the zoom will be on client position. The client can set to points(addres) A,B and the system will provide a route from point A to B. Another feture, the client could change vehicle to: Car,Cycling,walking.