I could see this being useful for anyone who works with equipment subject to overheating. I would be nice to snap a few photos to show that network equipment is running at the right temperature in an IDF closet. It also would be nice when working in a space with pipes to tell you if any of them are too hot to touch.
FLIR already makes a $250 thermal camera attachment for smartphones and $600+ stand alone handheld thermal cameras. So if you add in the fact that this is a full android smartphone and supposedly can be used underwater for up to an hour and survive a 5 foot drop onto concrete, it is a pretty cool package for $650.