Abstract: In an embodiment, an apparatus, such as a sensor package, includes a sensor, an antenna, and a power circuit. The package is configured for attachment to an object or a subject, for example a patient in need of clinical monitoring. The sensor package is configured to sense a condition or conditions related to the object or subject, and configured to generate a sense signal according to the sensed condition. The sensor patch may include a dual power source and means for switching between power sources, such as NFC and battery. The sensor patch may also include dual radios. As practiced, an NFC radio can be supplemented with a Bluetooth or other LAN radio for data logging. Systems for monitoring sensor patches may include methods for monitoring or tracking location of the patches.