A system for the collection, aggregation and analysis of location based crowd sourcing data includes a server that controls the distribution of crowd sourcing requests and workloads to a plurality of external mobile platforms. The server receives crowd sourcing queries from multiple parties and provides measurement requests to the mobile platforms, e.g., based on the location of the mobile platforms. Upon receipt of the measured contextual data from the mobile platforms, the server distributes information, such as the raw measured contextual data or an analysis of the measured contextual data, to the appropriate requesting parties in a secure manner. The mobile platform may receive a plurality of measurement requests from a remote server based on crowd sourcing queries from a plurality of parties. The mobile platform may measure and provide to the remote server contextual data in response to the plurality of measurement requests.