After swallowing, the pill travels through your digestive tract for a day or two collecting data such as:
- Gastric (stomach) emptying time
- Small bowel transit time
- Colon transit time
- Whole gut transit time
- Temperature
- Pressure patterns
- pH
I've included an image of the SmartPill capsule. It measures 26mm by 13mm (about 1 inch by 1/2 inch).
Source: SmartPill Corp.