Techniques for determining flow properties of a fluid in a fluidic device comprising a light source configured to generate a plurality of optical signals, tracers suspended in a fluid, a plurality of photonic devices, each including a photonic element and flow channel, and a measurement device configured to: determine a first measurement based on the plurality of optical signals and the tracers in a flow channel of a first photonic device of the plurality of photonic devices, determine a second measurement based on the plurality of optical signals and the tracers in a flow channel of a second photonic device of the plurality of photonic devices, and determine a property associated with a flow of the fluid or the tracers based on the first measurement and the second measurement.