Abstract: We can smell, taste, feel, hear and see the gifts of nature but we have always had that curiosity or a strong desire to measure those senses in a more systematic manner and record those values/store those values. Sound from a speaker is loud- This is the reading given by our ears which is one of the five sense organs, but we would like to measure it in terms of units like decibels dB, frequency Hz etc… This is necessary for systematic analysis. For this we need a sensor that is sensitive to the real time processes and their outcome, a processing unit, connectivity elements and output display/elucidation unit. In this paper we carry out real time measurements of %vol of vapour of a volatile liquid (Alcohol), Leakage of hazardous gasses like LPG, Climate-Humidity and temperature and the distance between the source and the obstacle using ultrasonic sensors. All these real time sensor data is monitored wirelessly using a third party developed Android application and installed into an Android OS powered Smartphone and stored into the internal or SD card memory (external memory) of the Smartphone. We have designed an android application named “Sense_graph” which can wirelessly record and monitor real time values. In this paper we also mention the key considerations in sensor selection and operation, they are Accuracy and Resolution, Precision, Sensitivity, Reliability, Response time, Practicality and Cost.

Keywords: Leakage of hazardous gasses like LPG, Climate-Humidity and temperature, ultrasonic sensors, Accuracy and Resolution, Precision, Sensitivity, Reliability, Response time, Practicality and Cost.