OK, so one of the great things about Android is how many attachments there are via the USB C port. There are not a lot of real choices here the two big ones are FLIR and Seek according to Digital Camera World and Industrial Reviews as well as TEquipment on Youtube
- Seek Thermal CompactPRO. This camera is better technically in all respects, it has a 320x240 imager and a 15Hz refresh rate (so it can't leave this country :-). But reading the Google Play Store reviews, it has issues with the application not really working. Also unlike the FLIR ONE Pro it is much smaller since it doesn't have an optical sensor and a battery inside of it. The Seek application does let you correct the parallax error from the image taken with the camera and the sensor or you can do this in software later.. And a long compatibility list of basically all the Pixels (but 6 is not listed). $340 at Amazon.
- FLIR ONE Pro. This is a relatively low resolution 120x160 imager, but the application works much better and it does work on the Pixel 6. Also there are third party applications that work with it, so apparently Teledyne/FLIR does provide support for just reading the camera. It also merges optical with the IR imager which is nice and has its own battery so is much bigger. $400 at Amazon. The compatibility list is tiny, but reading Google Play Store, it looksl like it works on the Pixel 6 at least. The biggest complaint is they stick a big logo on top of all their images and videos which is nice advertising for them and you apparently have to remove it by using a third party application. The other problem is the battery definitely dies.
- Hti HT-301. This is a 384x288 resolution device so a big bigger than the Seek Thermal CompactPro but does cost $700 at Amazon, but it does have a 25Hz refresh rate. The native application doesn't work well, but you can use Thermviewer that does cost $34. It has a relatively narrow 28 degree FOV and there is not automate image over IR blending, so you will have to do that manually by taking a regular photo and aligning it with the other image. Also, it doesn't record the heat at each point in the JPEG (there is a specific JPEG format for that). Also the native application has colors that are relative to the picture so you can't figure out the absolute temperature, although it does if the center point temperature, so you could figure outhe calibraiton.
- AGM Glory Pro. YOu can even get an entire phone with its own thermal imaging system built right in. It is old of course with a Snapdragon 480, but if you want a rugged dedicated device, this is it. $900 at Amazon.