No description available.

This presented work deals with crowdsourcing tools for mapping and filtering of data that are created by the Ushahidi, Inc. and ways of their use. Ushahidi and SwiftRiver platforms and hosted version of Ushahidi called Crowdmap are counted among the tools for crisis mapping; however, more and more they are also used for other topics or issues. The aim of this work is to subject to a critical point of view not only the Ushahidi platform as a tool, but also a number of significant or interesting projects in which it was used. Presented is also the recommendation, how to use Ushahidi to create a successful project and the other way round what to avoid, when you work with Ushahidi. The basic building elements of Ushahidi are crowdsourcing, citizen journalism, geospatial information, and in particular the work of volunteers. This work describes the role of these building elements in Ushahidi, and subjects to critical reflection also the problematic sides, which Ushahidi is struggling with. Following is the analysis of selected sample of Ushahidi and Crowdmap deployments, which deals with the thematic, geographical and time stratification of the maps in the sample. Some significant uses of Ushahidi with humanitarian and non-humanitarian purpose of the deployment are examined in the end.