Radioactivity Counter

★★★★★ This app is great it really works I've tested it against a Geiger Counter the readings were accurate to love it!!!

★★★★★ Not a novelty! Not sure on accuracy or sensitivity, but it worked a treat. My wife had treatment where she took radioactive iodine for a thyroid condition and the count showed at least 20 times the amount of background radiation near her throat as expected. I placed a small layer of aluminum foil held over the lens by tape. Make sure no light gets in i.e. test background count with and without a light shining on it.

★★★★★ Elegant and Powerful Surprisingly accurate when compared to a dedicated Geiger counter. Excellent idea and very well executed.

★★☆☆☆ Didn't work on Nexus 4, no reply to emails I bought the $4+ app, and installed it to a Nexus 4 with the back lens cover covered with 2 pieces of black electrical tape. I borrowed a real Geiger counter and some radioactive samples that read about 10-20x above background when very close to the sensor. One was tested even though a thin metal lid with both this app (and nexus 4) as well as the real Geiger counter. After following the instructions and allowing the app to calibrate, it settled on a background count around 20 (I tried it several times, and it was roughly 20 each time). The app does mention something about a 60-minute test but no amount of searching would allow me to figure out how to change that time. After calibrating (~20), tried detecting the samples. What would normally take the Geiger counter from ~20 cpm to ~500 cpm took this app from 20 up to 26. It is barely statistically significant. Reviewed the website, noting I should have had more than enough sensitivity to detect this. After failing to get useful results, I sent 2 emails to the developer from their site. Their site asks you to email them before you give them a one-star rating. After no reply in 2+ wks. (still nothing) I rated.