Microfluidics has been a versatile platform for sorting and sensing. Most sorting methods are based on optical techniques, such as identifying based on fluorescence. There is a growing field of mechanical-based sorting, through flow pinching, interactions with solid arrays (deterministic lateral displacement) or other methods that exploit density differences. However, these techniques require specialized microfabrication and their throughput will be limited by delicate microstructures. We deployed a novel and highly sensitive sensor based on metallic (Pd) nanoislands grown on graphene, that is imbedded in a flexible material (PDMS). These sensors are low-cost (<$1 per device), inherently low-power but are exquisitely sensitive (0.001%). These sensors measure a range elastohydrodynamic deformation which can result from changes in flow rate, viscosity or presence of particles. We can readily measure flow-rates from a variety of ranges, from 100’s of nL/min to liters/min. We discuss applications of this sensor in particle determination, viscometry and several elastohydrodynamic phenomena.