Kudu began with research looking at how to use mobile technology to make agricultural markets more effective in Uganda. From 2010 we started looking at past price data for agricultural produce in Uganda, and noticed large price discrepancies which indicated problems with efficiency in the market. Farmers faced problems in finding buyers for their produce, being threatened with spoilage of their goods when no buyers could be found and often having little negotiating power. Traders also faced uncertainty in being able to locate produce, relying on word-of-mouth networks. Mobile price advisory services provided some help, particularly to farmers, but seemed to have problems with accuracy and timeliness. Conventional auction or listings services were not accessible to the majority of farmers and traders in Uganda who have basic phones with SMS functionality only. The insight behind Kudu was that rather than providing a listing of items offered which buyers could bid on (known as a single auction), a different type of system called a double auction is more appropriate to users with basic phones. In this type of auction, buyers and sellers separately communicate their requirements and the prices they are willing to trade at. The system then periodically clears the market, matching compatible buyers and sellers. Therefore our users only have to send a single text message, and the system takes into account price, location and other factors to automatically find the best matches.