Gadget Watch: iPhone case lets you see heat

Remember the alien with heat vision in the movie "Predator"? You, too, can now stalk people in the jungle by their heat signatures—or check your home insulation for leaks, whichever is most useful to you.

FLIR Systems Inc. is launching its first consumer product, an iPhone jacket that contains a heat camera. Temperature differences show up in different colors on the screen. For instance, you can set it to show hotter things in yellow, medium-hot in red and cold in purple.

The FLIR One will cost $349, which compares with $995 and up for FLIR's professional thermal imagers. The resolution of the thermal image is low, but the jacket also contains a regular, visible-spectrum camera and overlays the images for a more detailed picture. The phone can record video or stills of the heat images.

WHAT YOU COULD USE IT FOR:

— Spot leaky insulation in the house.

— Detect moisture leaks in the house. Because it loses heat through evaporation, water looks cold.

— Beat your kids at hide-and-seek, "Predator"-style.

— Spot lurkers in the parking lot or wildlife at night.

— Crazy party shots in darkness.

— Unique selfies. "Look at me, I have a fever!"

AVAILABILITY: The FLIR One will launch this spring for the iPhone 5 and 5S. It won't work with the 5C. An Android model will be available later this year.

THE ACCURACY: The thermal camera can detect temperature differences of about one-tenth of a Fahrenheit degree, and the temperature readout is accurate to within 2 degrees.