Henry Parkman, a gastroenterologist at Temple University School of Medicine in Philadelphia, who is a member of SmartPill's scientific advisory board and has tested the device in patients, says it may eventually be used for other disorders of the GI tract.

Gastroparesis, which can cause heartburn, vomiting, and loss of appetite, is most common in patients with diabetes and neurological disorders such as Parkinson's disease. Currently, the best test for gastroparesis is to have patients eat a meal tagged with a radioisotope, and to monitor them for several hours as the food passes through their digestive system. Clinicians also use long catheters with pressure sensors at the end to measure contractions in the digestive system. Parkman says the new device would be less invasive and inconvenient, and could be used in doctor's offices, when other techniques are not available.

But the ingestible sensor technology has its skeptics. Nonko Pehlivanov, a gastroenterologist at the University of Texas Medical Branch in Galveston, says that the current methods for diagnosing gastroparesis are invasive and time-consuming. But he says the new device hasn't yet proven it's as accurate as them. One of the fundamental problems with ingestible devices is that they're continuously on the move, which means they can only gather passing snapshots of places. "Sometimes you need prolonged information at a certain point in the GI tract," Pehlivanov says. And for that, invasive techniques are still needed.