The Thermal Master P3 is a thermal camera designed to plug directly into an iPhone or Android device through the phone’s USB-C port. While it’s a little on the pricey side it does offer some great features and has some useful macro features.
Check it out in my latest video review!
You can find one over at Amazon (compensated affiliate link). Once connected and the companion app is installed, the camera functions as a macro thermal imager—it’s clearly optimized for close-up inspections rather than broad outdoor scenes. It’s the kind of tool you’d use to check an electrical panel, a circuit board, or in my case, a Raspberry Pi, rather than searching for animals in the woods.
It can be attached facing either direction and even accommodates some thicker phone cases thanks to its extended connector, though not every case will fit comfortably. For older iPhones, there’s a lightning adapter included. When using the lightning adapter, the setup feels a bit unstable, so a short extension cable might be a better option.
There’s a focus ring built in, which helps bring small components into sharper view. The sensor itself is very small, with a native resolution of 256×192. The app offers an AI-enhanced mode that upscales to 512×384, but even then, fine detail is limited. The best results come when the camera is positioned close to the subject.
While testing, I filmed my Raspberry Pi booting up and watched the components warm in real time. I also pointed it at a stovetop to see how it handled extreme temperatures. The app includes built-in burn-in protection that reduces exposure to high heat sources, prompting me to back off a bit. Temperature ranges can be adjusted within the app, with one mode for lower temperatures (-4 °F to 302 °F) and another for higher ones (212 °F to 1,022 °F). You can’t combine the two ranges, but for most household or electronics projects, the preset bands are sufficient. A scale overlay can be toggled on to display minimum and maximum readings in real time.
I experimented with the camera around the house—tracking hot water lines, scanning my electrical panel, and exploring different color modes. The app provides several palette options such as white hot, black hot, and various false-color schemes. There’s also a split-view mode that overlays a standard camera image to help identify what you’re looking at when the thermal view alone doesn’t offer enough definition. Users can even draw shapes on-screen to isolate temperature readings from specific areas—useful for monitoring different components within the frame.
Although it costs less than dedicated professional thermal imagers, the device isn’t meant for scientific precision. The manual includes some reference values for emissivity correction, but calibration is limited, and readings shouldn’t be treated as exact. What it does well is provide quick visual confirmation of heat distribution. It’s compact, fits easily in a pocket, and draws power directly from the phone. For spotting hot spots on a breaker panel or verifying that a circuit board component isn’t overheating, it’s a handy, portable option that fills the gap between hobby gear and higher-end tools.
Disclosure: The camera was sent to the channel free of charge. No other compensation was received and no one reviewed or approved this content prior to uploading. All opinions are my own.