IBM is testing a paper test strip which, when analysed with an app on a standard smartphone, could reduce the time and cost for farmers trying to work out how to prepare soil for planting, treat water, or maintain optimal growth of crops. The card is about the size of a business card, and changes colour in specific patterns to measure pH, nitrogen dioxide, aluminium and other chemicals necessary for (or best avoided) for healthy plant growth. The app allows immediate, precise diagnosis (the camera is more a accurate colour sensor than the human eye), and aggregated data can help governments monitor fertilizer/chemical use.
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The IBM AgroPad is a paper testing strip that, when combined with a mobile app, relies on machine vision to measure the precise amounts of chemicals in samples of water and soil.