Olive orchard plays a key role in the economy of Andalusia (Southern Spain). It is also the most representative and extensive crop in that region. In fact, for that reason, it is the crop to which more water is allocated in the Guadalquivir River Basin. Additionally, its fertilization is based on the farmers experience which leads to inaccuracy and unnecessary fertilizers application. This over-fertilization, which is often of Nitrogen, causes significant impacts on soils, water and atmosphere, which threats the biosystem sustainability. At this juncture, olive orchard irrigation using reclaimed water arises as an alternative of the traditional water sources. Nevertheless, its management is more complicated since the water is already a nutrient carrier. In this work, a mobile application for Android devices has been developed. The application aims to provide farmers and technicians of a user-friendly tool which facilitates the fertigation management using reclaimed water for olive orchard irrigation. The mobile application has been used in a commercial farm, reducing the application of additional fertilizers. This leads to both environmental benefits and financial cost reductions.