Smart labels are devices with sensors which can interact with existing RIFD (radio frequency identification) infrastructure. Sensors can be integrated in tag chips or can be connected externally. Smart labels have been used in numerous applications to improve transportation and product control. In this work we have summarized some of our applications in which smart tags are used to enhance interaction with environment. Smart labels can be used to control temperature in fish supply cold chain, control fruit ripening process in plantation, control medical staff disinfection in hospitals or be used to measure sweat contents on a patch worn on human skin. We presented a smart tag with digital sensor interface and two example sensor nodes. First with 4 environmental sensors and second with accelerometer and gyroscope. The sensor nodes have been used for wireless data collection.