Compact systems, compact devices and methods are provided to sense changes in luminescence due to environmental influences on a luminescent material. Such systems, devices and methods may be implemented in a compact device, e.g., an integrated circuit package, which may be incorporated into or attached to a device, such as a smartphone, watch, flashlight, vehicle, etc. The systems, devices, and methods described herein are useful in sensing luminescence, as well as changes in luminescence that are indicative of environmental influences, such as the presence and concentration of a gas or chemical, ambient temperature, pressure, light, etc., in an area surrounding a luminescent material included in a compact device.