Embodiments provide devices, systems and methods for measuring a gastric emptying (GE) parameter (GEP). Many embodiments provide a swallowable capsule having three electrodes one covered by a coating which remains in the stomach but is degraded in the small intestine (SI). The electrodes are coupled to circuitry such that when the capsule is in the stomach, current flow occurs between the first two electrodes generating a first signal and in the SI current flow occurs between the second and now uncovered third electrode generating a second signal. These two signals can be transmitted and analyzed externally or by an internal controller to determine a GEP e.g., GE time. The patient may wear an external device configured to receive and analyze the signals to determine GE time. Embodiments of the invention may be used to diagnose gastroparesis and provide patient's information on when to eat meals or administer insulin after eating.