A free app for Android, by Optivelox.
RadMeter is the most powerful, easy-to-use, and affordable Geiger meter. It allows you to measure and track the amount of radiation in the air, on your skin, or anywhere else. It uses the newest technology to measure the radiation, which is more accurate and reliable than previous methods.
RadMeter can also track the amount of radiation you are exposed to and measure the rate of change of the radiation level. You can save the data to a log file so you can later analyze the results.
You can also choose to use the built-in sensor or define your own sensor and add it to the database.
