An ingestible apparatus for collecting samples from a target area of a gastrointestinal tract of a human or mammal and/or for delivering a health-related fluid thereto. The ingestible apparatus has a housing comprising at least one first port and at least a volume-changeable first compartment fluidly communicable with the at least one first port, an actuation assembly for changing the volume of the first compartment for collecting the samples and/or discharging the health-related fluid through the at least one first port, a delay structure for delaying the actuation assembly to change the volume of the first compartment until the ingestible apparatus is at or about the target area, and a circuit structure for detecting arrival of the ingestible apparatus at the target area and for detecting an end of the sample collecting and/or the health-related-fluid discharging.
