The hti app does have enough sharpening to make it look a bit like msx (and slightly lower resolution) is being applied, but 'tis absolutely not the case 😉
Otherwise I agree 100% all of the above posts. Therm viewer does provide a much less molested image in general, and the extra NUC (eraser mode) can be quite handy for getting rid of the slight lens aberration that isn't always apparent any way.
I use both apps depending on mood (tho I use the modified version posted on here that removes the hti watermark). As offensive as the hti sharpening can be, it does handle dynamic range a bit better than therm viewer, YMMV.
The extra colour profiles in thermviewer at pretty handy, "enhanced" is great for scenes with very little temperature variation, turns pitch black night time into detailed B&W CCTV 🙂 "edge detect" is like a focus tuning tool, adjust till the desired object has a single outline and focus is nailed.
Whatever flavour you prefer, it sounds like there's little doubt that this is the camera for you, every box ticked and negatives not such a problem 😉 as for durability, the USB is the weak point, especially hanging off the USB port of a phone... I actually had to replace the plug and fpc connector on mine for $45us 😲 although the replacement seems to be holding up better, luck of the draw or slightly improved design? YMMV, again.
Get a short right angle USB-C extension cable and sort out some kind of holder or clamp to put it on the back of the phone, 3d printing probably the best option there.
Also, a lot of the stills posted on here and in my gallery can look a little average, it's bloody hard to tap the photo button in either app without causing camera shake, but the videos don't suffer from anything of the sort.
Cheers