Crowdsourcing is a sourcing model in which individuals or organisations use contributions from Internet users to obtain services or ideas. It has become popularised by the likes of Uber, Airbnb. The democratisation of services has enabled new entrants to a marketplace with low or even zero investment. Within retail, crowdsourcing is starting to be used to drive down costs of last mile delivery, something which until recently has been monopolised by delivery firms such as DHL and UPS.