It turns out that the resolution of the thermal camera is 80 by 60 pixels but this is merged with a 640 by 480 pixel visible light camera and the image is enhanced depending on which mode you use. The image below is a composite image used by FLIR for promotion.
You can see the softness of the thermal information but I have to admit the blend with the visual image makes for a quite usable result.
The cost in the US is $350 and you have to use an iPhone 5 or 5s. The device will not fit on either iPhone 6 and it would seem that FLIR have no plans to produce a new one. That was always the risk but this still brings thermal imaging into a completely new area of use, appealing to small businesses and hobbyists alike.
Gizmodo got their hands on one in August and explain just what you might want to do with it (if you don't know already). They also did a review, but they were unsure whether it's worth the money. Given the usual way tech prices inflate as they cross the Atlantic that may be a bigger issue over here in the UK. That said, to echo one of the commentators on the review, it's still cheap for a thermal imager.