Facile Sendi is part of the Facila software system for effective registration of manual, numeric observations. It is primarily designed with hydrology and meteorology in mind, but any manual observed reading (meter readings, levels, gauges, or whatnot) might be defined in the system. Facile Sendi connects to a lightweight backend named Facile Ricevi. Facile Ricevi also includes a web-based administration tool that keep track of observers, observation sites and the data ingested by the observers.