Smart Geiger, a portable radiation detection and measuring instrument. It is a compact, keychain-style device designed for personal use. It detects and measures ionizing radiation using a Geiger-Müller tube. The device functions as a personal radiation detector and dosimeter by connecting to a smartphone's headphone jack. Functionality: It measures general radiation exposure levels (Gamma and X-rays) over a period of time, such as an hour, rather than providing instant "snapshot" readings. Usage: Users must download a specific app (e.g., "Smart Geiger Pro" or "FTLAB") from an app store (iOS or Android) to view the measurements. Portability: The device is small and designed to be easily carried, often with a keychain loop as seen in the image. New See photos for more details