The PositionOptions.maximumAge property is a positive long value indicating the maximum age in milliseconds of a possible cached position that is acceptable to return. If set to 0, it means that the device cannot use a cached position and must attempt to retrieve the real current position. If set to Infinity the device must return a cached position regardless of its age.
The PositionOptions.timeout property is a positive long value representing the maximum length of time (in milliseconds) the device is allowed to take in order to return a position. The default value is Infinity, meaning that getCurrentPosition() won't return until the position is available.
The Geolocation.watchPosition() method is used to register a handler function that will be called automatically each time the position of the device changes. You can also, optionally, specify an error handling callback function.