Sensing devices including flexible and stretchable fabric-based pressure sensors, may be associated with or incorporated in garments intended to be worn against a body surface (directly or indirectly), or may be associated with other types of flexible substrates, such as sheet-like materials, bandages and other materials that contact the body (directly or indirectly), and may be provided as independently positionable sensor components. Systems and methods for storing, communicating, processing, analyzing and displaying data collected by sensor components for remote monitoring of conditions at body surfaces, or within the body, are also disclosed. Sensors and sensor systems provide substantially real-time feedback relating to current body conditions and may provide notifications or alerts to users, caretakers and/or clinicians, enabling early intervention when conditions indicate intervention is appropriate.