The services are predefined by the provider and can be used according the mandatory licence. The services can be commercial (e.g. Austrian Map) or at no charges (e.g. Google Maps), often depending of the kind of usage.
Database entries occur after some time consuming quality check. Shops can buy for better product placement as "Point of Interest".
Open source products (e.g. Open Street Map) may be used by anybody. They also may be modified by anybody after some kind of registration. In general, the license only requires to declare the source of information and not to use the free data in a commercial manner.
Data are of heterogenous quality because of much people delivering without any supervisor interaction. In cities, the data have better quality than in the mountains. The user declare "Points of Interest" in accordance to their own rating. The shop can place promotions without supervision.
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