Always get a standalone device. Never buy equipment that requires an app to function.

the “more info” so you dont have to go to reddit

They have - it's really pissed me off and had a fruitless discussion with their support about it. It was part of the specification it was sold with and they've removed this functionality it via software update which makes it effectively useless for surveying ; unless you want to take lots of images and post-process the scale and analyse off-site which is far more labour intensive and not why I bought the device. They've said they wont resolve and want me to buy a new device which Ive pointed out is basically mafia style extortion but they don't seem to give a toss. Stated the only option is to buy a new full pro device - they offer a "voucher" for a non warranty replacement but it only changes the price in their web store to be the same as the non-RRP competitve price elsewhere. I will be avoiding FLIR products like the plague in the future as deliberately crippling a device to force users to upgrade is grossly un-ethical behavior (which has generally resulted in anti-trust cases that have been won in mass market products ...) Any suggestions for competitor devices to look at gratefully received!

So,... What's the Chinese one?

can you downgrade the software or anything?

The strange thing is that I also have a FLIRone pro (Android version with USB-C in my case), but that one still has the scale lock feature. There's also an alternative app by a 3rd party developer if I'm not mistaken.