Fluid-based no-moving part logic devices are constructed from complex sequences of micro- and nanofluidic channels, on-demand bubble/droplet modulators and generators for programming the devices, and micro- and nanofluidic droplet/bubble memory elements for storage and retrieval of biological or chemical elements. The input sequence of bubbles/droplets encodes information, with the output being another sequence of bubbles/droplets or on-chip chemical synthesis. For performing a set of reactions/tasks or process control, the modulators can be used to program the device by producing a precisely timed sequence of bubbles/droplets, resulting in a cascade of logic operations within the micro- or nanofluidic channel sequence, utilizing the generated droplets/bubbles as a control. The devices are based on the principle of minimum energy interfaces formed between the two fluid phases enclosed inside precise channel geometries. Various devices, including logic gates, non-volatile bistable memory, ring oscillators, bubble synchronizers, analysis chips, sample collectors, and printers have been designed.