DIY thermal imaging with old phone cameras—real or wishful thinking?

So I've been reading some stuff online (Reddit, YouTube, the usual rabbit holes) about people using old smartphones with some kind of hack to pick up thermal signatures. Sounds brilliant in theory - everyone's got an old phone lying about.

The claim is that certain older phone sensors (especially some Samsung and Motorola units from 2015-2017) have slightly better near-infrared sensitivity, and if you remove or modify the IR filter, you can use them with an external thermal source or even pick up ambient heat.

I've got an old Moto G4 sitting in a drawer. Before I start taking it apart and potentially binning it, has anyone here actually tried this? Is it legitimate DIY thermal imaging or am I about to waste an afternoon watching YouTube videos and destroy a perfectly serviceable phone?

It's real in the sense that you CAN modify phones to be more IR-sensitive, but the results are usually pretty terrible. You get a grainy, low-res thermal-ish image that's not much better than just using your eyes in darkness. The issue is the sensor itself isn't designed for thermal imaging - it's a hack, not a solution.

If you want proper thermal, the FLIR One cameras (around £200-300) are worth the investment. Or wait for prices on older FLIR models to drop.

I did this about two years ago with an iPhone 6 and honestly it was a fun experiment but useless for actual investigation work. The image was so noisy and low-contrast that I could barely make out shapes. Sent it back together and got a proper thermal unit instead.

The Samsung route is slightly better than iPhone because some Galaxy models had different sensor specs, but you're still looking at pretty limited results. If you're doing it as a hobby project for learning, go for it. If you need something that actually works, don't.