Thermal Light is the first of its kind app that uses black body radiation of an object (iron/steel, copper, ceramics) to determine temperatures between 1000F and 2700F. Very hot objects irradiate light; the app uses this light to determine the temperature between 1000 and 2700F. The app has been calibrated against a certified IR thermometer. Why spend $900 for an IR or optical thermometer when you can convert your iPhone to do the same thing? This is great for knowing the temperature of your steel for working. Temperature increments are 50F.
Please go to support website for more details at http://houseofficer.com/forgingtemperature