Methods and apparatus for monitoring remotely located objects with a system including at least one master data collection unit, remote sensor units, and a central data collection server are described. The master unit is configured to monitor any object, mobile or stationary, including monitoring multiple remote sensor units associated with the monitored objects. The master unit may be in a fixed location or attached to a mobile object. The master unit is configured for monitoring objects that enter and leave an area. The master unit may act as a parent controller for one or more child devices including remote sensors or monitors of measurable conditions including environmental conditions, substance identification, product identification, and/or biometric identification. The master unit may discover remote sensor units as they enter or leave the area where the master unit is located. The master unit can be remotely reprogrammed such as with authenticated instructions.