This was a very simple app for farmers. It was built in 2010. It provided growers with an easy reference tool to support higher yields. The app showed the removal rates of 36 different crops for five key nutrients - nitrogen, phosphate, potash, magnesium and sulfur. The results listed the amount of nutrients removed when harvesting the crop. It also indicated the nutrients removed when stalks, stover or straw are harvested from the field.
As for my part of this project, here is what I was responsible for: the functional requirements, use case scenarios, interaction design, on-farm user test and the final visual design.
As simple as it was, testing on site with farmers revealed a big problem we did not anticipate. Quite often there was no signal on the farm. We revised the app to use off-line storage and everything ended up okay.