oh wow, an older topic-
It's available on the Website- and is decent
I use therm apps heavily and use it occasionally- not as frequent as ThermAppPlus, but that one is no longer on the store as well, while ThermViewer is still on available on their own website, for now.
https://thermviewer.com/It's not bad at all- multiple palettes, options to tweak the span a little bit, and a few other things.
Better than the default app, since it lets you control some aspects of it