The alternative routes provided can be changed depending on criteria. For example, code the streets was tested in both Amsterdam and Helsinki. In Amsterdam, the objective was to provide more safety by letting setting the system up to avoid certain areas at certain times. For example: to avoid school zones at busy hours.
In Helsinki, the system was set up to avoid congestion by gathering data to discover incentives people have to leave home later or to take another route.
By the end of both experiments 40% of the school zones were safer, because 40% of the people chose to avoid the school areas.